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CVE-2025-71066 (GCVE-0-2025-71066)

Vulnerability from cvelistv5 – Published: 2026-01-13 15:31 – Updated: 2026-08-05 12:11
VLAI
Title
net/sched: ets: Always remove class from active list before deleting in ets_qdisc_change
Summary
In the Linux kernel, the following vulnerability has been resolved: net/sched: ets: Always remove class from active list before deleting in ets_qdisc_change zdi-disclosures@trendmicro.com says: The vulnerability is a race condition between `ets_qdisc_dequeue` and `ets_qdisc_change`. It leads to UAF on `struct Qdisc` object. Attacker requires the capability to create new user and network namespace in order to trigger the bug. See my additional commentary at the end of the analysis. Analysis: static int ets_qdisc_change(struct Qdisc *sch, struct nlattr *opt, struct netlink_ext_ack *extack) { ... // (1) this lock is preventing .change handler (`ets_qdisc_change`) //to race with .dequeue handler (`ets_qdisc_dequeue`) sch_tree_lock(sch); for (i = nbands; i < oldbands; i++) { if (i >= q->nstrict && q->classes[i].qdisc->q.qlen) list_del_init(&q->classes[i].alist); qdisc_purge_queue(q->classes[i].qdisc); } WRITE_ONCE(q->nbands, nbands); for (i = nstrict; i < q->nstrict; i++) { if (q->classes[i].qdisc->q.qlen) { // (2) the class is added to the q->active list_add_tail(&q->classes[i].alist, &q->active); q->classes[i].deficit = quanta[i]; } } WRITE_ONCE(q->nstrict, nstrict); memcpy(q->prio2band, priomap, sizeof(priomap)); for (i = 0; i < q->nbands; i++) WRITE_ONCE(q->classes[i].quantum, quanta[i]); for (i = oldbands; i < q->nbands; i++) { q->classes[i].qdisc = queues[i]; if (q->classes[i].qdisc != &noop_qdisc) qdisc_hash_add(q->classes[i].qdisc, true); } // (3) the qdisc is unlocked, now dequeue can be called in parallel // to the rest of .change handler sch_tree_unlock(sch); ets_offload_change(sch); for (i = q->nbands; i < oldbands; i++) { // (4) we're reducing the refcount for our class's qdisc and // freeing it qdisc_put(q->classes[i].qdisc); // (5) If we call .dequeue between (4) and (5), we will have // a strong UAF and we can control RIP q->classes[i].qdisc = NULL; WRITE_ONCE(q->classes[i].quantum, 0); q->classes[i].deficit = 0; gnet_stats_basic_sync_init(&q->classes[i].bstats); memset(&q->classes[i].qstats, 0, sizeof(q->classes[i].qstats)); } return 0; } Comment: This happens because some of the classes have their qdiscs assigned to NULL, but remain in the active list. This commit fixes this issue by always removing the class from the active list before deleting and freeing its associated qdisc Reproducer Steps (trimmed version of what was sent by zdi-disclosures@trendmicro.com) ``` DEV="${DEV:-lo}" ROOT_HANDLE="${ROOT_HANDLE:-1:}" BAND2_HANDLE="${BAND2_HANDLE:-20:}" # child under 1:2 PING_BYTES="${PING_BYTES:-48}" PING_COUNT="${PING_COUNT:-200000}" PING_DST="${PING_DST:-127.0.0.1}" SLOW_TBF_RATE="${SLOW_TBF_RATE:-8bit}" SLOW_TBF_BURST="${SLOW_TBF_BURST:-100b}" SLOW_TBF_LAT="${SLOW_TBF_LAT:-1s}" cleanup() { tc qdisc del dev "$DEV" root 2>/dev/null } trap cleanup EXIT ip link set "$DEV" up tc qdisc del dev "$DEV" root 2>/dev/null || true tc qdisc add dev "$DEV" root handle "$ROOT_HANDLE" ets bands 2 strict 2 tc qdisc add dev "$DEV" parent 1:2 handle "$BAND2_HANDLE" \ tbf rate "$SLOW_TBF_RATE" burst "$SLOW_TBF_BURST" latency "$SLOW_TBF_LAT" tc filter add dev "$DEV" parent 1: protocol all prio 1 u32 match u32 0 0 flowid 1:2 tc -s qdisc ls dev $DEV ping -I "$DEV" -f -c "$PING_COUNT" -s "$PING_BYTES" -W 0.001 "$PING_DST" \ >/dev/null 2>&1 & tc qdisc change dev "$DEV" root handle "$ROOT_HANDLE" ets bands 2 strict 0 tc qdisc change dev "$DEV" root handle "$ROOT_HANDLE" ets bands 2 strict 2 tc -s qdisc ls dev $DEV tc qdisc del dev "$DEV" parent ---truncated---
Severity
7.8 (High)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
7.5 (High)
CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:C/C:H/I:H/A:H
SSVC
Exploitation: none Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-05-22 03:55 UTC
CWE
  • CWE-362 - Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: ae2659d2c670252759ee9c823c4e039c0e05a6f2 , < 062d5d544e564473450d72e6af83077c2b2ff7c3 (git)
Affected: e25bdbc7e951ae5728fee1f4c09485df113d013c , < c7f6e7cc14df72b997258216e99d897d2df0dbbd (git)
Affected: de6d25924c2a8c2988c6a385990cafbe742061bf , < a75d617a4ef08682f5cfaadc01d5141c87e019c9 (git)
Affected: de6d25924c2a8c2988c6a385990cafbe742061bf , < 9987cda315c08f63a02423fa2f9a1f6602c861a0 (git)
Affected: de6d25924c2a8c2988c6a385990cafbe742061bf , < 06bfb66a7c8b45e3fed01351a4b087410ae5ef39 (git)
Affected: de6d25924c2a8c2988c6a385990cafbe742061bf , < 45466141da3c98a0c5fa88be0bc14b4b6a4bd75c (git)
Affected: de6d25924c2a8c2988c6a385990cafbe742061bf , < ce052b9402e461a9aded599f5b47e76bc727f7de (git)
Affected: 5.10.83 , < 5.10.248 (semver)
Affected: 5.15.6 , < 5.15.198 (semver)
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Linux Linux Affected: 5.16
Unaffected: 0 , < 5.16 (semver)
Unaffected: 5.10.248 , ≤ 5.10.* (semver)
Unaffected: 5.15.198 , ≤ 5.15.* (semver)
Unaffected: 6.1.160 , ≤ 6.1.* (semver)
Unaffected: 6.6.120 , ≤ 6.6.* (semver)
Unaffected: 6.12.64 , ≤ 6.12.* (semver)
Unaffected: 6.18.3 , ≤ 6.18.* (semver)
Unaffected: 6.19 , ≤ * (original_commit_for_fix)
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          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: ets: Always remove class from active list before deleting in ets_qdisc_change\n\nzdi-disclosures@trendmicro.com says:\n\nThe vulnerability is a race condition between `ets_qdisc_dequeue` and\n`ets_qdisc_change`.  It leads to UAF on `struct Qdisc` object.\nAttacker requires the capability to create new user and network namespace\nin order to trigger the bug.\nSee my additional commentary at the end of the analysis.\n\nAnalysis:\n\nstatic int ets_qdisc_change(struct Qdisc *sch, struct nlattr *opt,\n                          struct netlink_ext_ack *extack)\n{\n...\n\n      // (1) this lock is preventing .change handler (`ets_qdisc_change`)\n      //to race with .dequeue handler (`ets_qdisc_dequeue`)\n      sch_tree_lock(sch);\n\n      for (i = nbands; i \u003c oldbands; i++) {\n              if (i \u003e= q-\u003enstrict \u0026\u0026 q-\u003eclasses[i].qdisc-\u003eq.qlen)\n                      list_del_init(\u0026q-\u003eclasses[i].alist);\n              qdisc_purge_queue(q-\u003eclasses[i].qdisc);\n      }\n\n      WRITE_ONCE(q-\u003enbands, nbands);\n      for (i = nstrict; i \u003c q-\u003enstrict; i++) {\n              if (q-\u003eclasses[i].qdisc-\u003eq.qlen) {\n\t\t      // (2) the class is added to the q-\u003eactive\n                      list_add_tail(\u0026q-\u003eclasses[i].alist, \u0026q-\u003eactive);\n                      q-\u003eclasses[i].deficit = quanta[i];\n              }\n      }\n      WRITE_ONCE(q-\u003enstrict, nstrict);\n      memcpy(q-\u003eprio2band, priomap, sizeof(priomap));\n\n      for (i = 0; i \u003c q-\u003enbands; i++)\n              WRITE_ONCE(q-\u003eclasses[i].quantum, quanta[i]);\n\n      for (i = oldbands; i \u003c q-\u003enbands; i++) {\n              q-\u003eclasses[i].qdisc = queues[i];\n              if (q-\u003eclasses[i].qdisc != \u0026noop_qdisc)\n                      qdisc_hash_add(q-\u003eclasses[i].qdisc, true);\n      }\n\n      // (3) the qdisc is unlocked, now dequeue can be called in parallel\n      // to the rest of .change handler\n      sch_tree_unlock(sch);\n\n      ets_offload_change(sch);\n      for (i = q-\u003enbands; i \u003c oldbands; i++) {\n\t      // (4) we\u0027re reducing the refcount for our class\u0027s qdisc and\n\t      //  freeing it\n              qdisc_put(q-\u003eclasses[i].qdisc);\n\t      // (5) If we call .dequeue between (4) and (5), we will have\n\t      // a strong UAF and we can control RIP\n              q-\u003eclasses[i].qdisc = NULL;\n              WRITE_ONCE(q-\u003eclasses[i].quantum, 0);\n              q-\u003eclasses[i].deficit = 0;\n              gnet_stats_basic_sync_init(\u0026q-\u003eclasses[i].bstats);\n              memset(\u0026q-\u003eclasses[i].qstats, 0, sizeof(q-\u003eclasses[i].qstats));\n      }\n      return 0;\n}\n\nComment:\nThis happens because some of the classes have their qdiscs assigned to\nNULL, but remain in the active list. This commit fixes this issue by always\nremoving the class from the active list before deleting and freeing its\nassociated qdisc\n\nReproducer Steps\n(trimmed version of what was sent by zdi-disclosures@trendmicro.com)\n\n```\nDEV=\"${DEV:-lo}\"\nROOT_HANDLE=\"${ROOT_HANDLE:-1:}\"\nBAND2_HANDLE=\"${BAND2_HANDLE:-20:}\"   # child under 1:2\nPING_BYTES=\"${PING_BYTES:-48}\"\nPING_COUNT=\"${PING_COUNT:-200000}\"\nPING_DST=\"${PING_DST:-127.0.0.1}\"\n\nSLOW_TBF_RATE=\"${SLOW_TBF_RATE:-8bit}\"\nSLOW_TBF_BURST=\"${SLOW_TBF_BURST:-100b}\"\nSLOW_TBF_LAT=\"${SLOW_TBF_LAT:-1s}\"\n\ncleanup() {\n  tc qdisc del dev \"$DEV\" root 2\u003e/dev/null\n}\ntrap cleanup EXIT\n\nip link set \"$DEV\" up\n\ntc qdisc del dev \"$DEV\" root 2\u003e/dev/null || true\n\ntc qdisc add dev \"$DEV\" root handle \"$ROOT_HANDLE\" ets bands 2 strict 2\n\ntc qdisc add dev \"$DEV\" parent 1:2 handle \"$BAND2_HANDLE\" \\\n  tbf rate \"$SLOW_TBF_RATE\" burst \"$SLOW_TBF_BURST\" latency \"$SLOW_TBF_LAT\"\n\ntc filter add dev \"$DEV\" parent 1: protocol all prio 1 u32 match u32 0 0 flowid 1:2\ntc -s qdisc ls dev $DEV\n\nping -I \"$DEV\" -f -c \"$PING_COUNT\" -s \"$PING_BYTES\" -W 0.001 \"$PING_DST\" \\\n  \u003e/dev/null 2\u003e\u00261 \u0026\ntc qdisc change dev \"$DEV\" root handle \"$ROOT_HANDLE\" ets bands 2 strict 0\ntc qdisc change dev \"$DEV\" root handle \"$ROOT_HANDLE\" ets bands 2 strict 2\ntc -s qdisc ls dev $DEV\ntc qdisc del dev \"$DEV\" parent \n---truncated---"
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              "value": "AV:L - Exploitation requires local rtnetlink qdisc configuration and locally generated traffic reaching the ETS dequeue path.\nAC:L - The attacker controls both racing paths by issuing qdisc changes while driving packet dequeue, and can deterministically create the stale active-list state. Although the UAF window is narrow, preemptible, RT, or virtualized scheduling makes it plausible, and the higher-severity tie-break requires L.\nPR:L - RTM_NEWQDISC requires CAP_NET_ADMIN in the target network namespace. An unprivileged user can obtain that capability by creating user and network namespaces on deployments permitting unprivileged user namespaces.\nUI:N - No victim action is required after the attacker configures ETS and generates concurrent traffic.\nS:U - The corruption and resulting kernel compromise occur within the Linux kernel\u2019s existing security authority; standard namespace escape or kernel privilege escalation does not change CVSS scope.\nC:H - The freed Qdisc can be reclaimed with attacker-influenced contents and dereferenced through its operations pointer, supporting kernel memory disclosure primitives.\nI:H - The UAF reaches an indirect peek function call through the freed Qdisc operations pointer, making control-flow hijacking and arbitrary kernel modification defensible.\nA:H - The flaw demonstrably causes a KASAN use-after-free or NULL-pointer kernel oops and can produce a kernel panic."
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    "dateUpdated": "2026-08-05T12:11:49.113Z",
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      "title": "net/sched: ets: Always remove class from active list before deleting in ets_qdisc_change",
      "url": "https://msrc.microsoft.com/csaf/vex/2026/msrc_cve-2025-71066.json",
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                "vendor": "Linux",
                "versions": [
                  {
                    "lessThan": "062d5d544e564473450d72e6af83077c2b2ff7c3",
                    "status": "affected",
                    "version": "ae2659d2c670252759ee9c823c4e039c0e05a6f2",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "c7f6e7cc14df72b997258216e99d897d2df0dbbd",
                    "status": "affected",
                    "version": "e25bdbc7e951ae5728fee1f4c09485df113d013c",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "a75d617a4ef08682f5cfaadc01d5141c87e019c9",
                    "status": "affected",
                    "version": "de6d25924c2a8c2988c6a385990cafbe742061bf",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "9987cda315c08f63a02423fa2f9a1f6602c861a0",
                    "status": "affected",
                    "version": "de6d25924c2a8c2988c6a385990cafbe742061bf",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "06bfb66a7c8b45e3fed01351a4b087410ae5ef39",
                    "status": "affected",
                    "version": "de6d25924c2a8c2988c6a385990cafbe742061bf",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "45466141da3c98a0c5fa88be0bc14b4b6a4bd75c",
                    "status": "affected",
                    "version": "de6d25924c2a8c2988c6a385990cafbe742061bf",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "ce052b9402e461a9aded599f5b47e76bc727f7de",
                    "status": "affected",
                    "version": "de6d25924c2a8c2988c6a385990cafbe742061bf",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "5.10.248",
                    "status": "affected",
                    "version": "5.10.83",
                    "versionType": "semver"
                  },
                  {
                    "lessThan": "5.15.198",
                    "status": "affected",
                    "version": "5.15.6",
                    "versionType": "semver"
                  }
                ]
              },
              {
                "defaultStatus": "affected",
                "product": "Linux",
                "programFiles": [
                  "net/sched/sch_ets.c"
                ],
                "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                "vendor": "Linux",
                "versions": [
                  {
                    "status": "affected",
                    "version": "5.16"
                  },
                  {
                    "lessThan": "5.16",
                    "status": "unaffected",
                    "version": "0",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "5.10.*",
                    "status": "unaffected",
                    "version": "5.10.248",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "5.15.*",
                    "status": "unaffected",
                    "version": "5.15.198",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "6.1.*",
                    "status": "unaffected",
                    "version": "6.1.160",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "6.6.*",
                    "status": "unaffected",
                    "version": "6.6.120",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "6.12.*",
                    "status": "unaffected",
                    "version": "6.12.64",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "6.18.*",
                    "status": "unaffected",
                    "version": "6.18.3",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "*",
                    "status": "unaffected",
                    "version": "6.19",
                    "versionType": "original_commit_for_fix"
                  }
                ]
              }
            ],
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
          }
        ],
        "cveTags": [],
        "descriptions": [
          {
            "lang": "en",
            "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: ets: Always remove class from active list before deleting in ets_qdisc_change\n\nzdi-disclosures@trendmicro.com says:\n\nThe vulnerability is a race condition between `ets_qdisc_dequeue` and\n`ets_qdisc_change`.  It leads to UAF on `struct Qdisc` object.\nAttacker requires the capability to create new user and network namespace\nin order to trigger the bug.\nSee my additional commentary at the end of the analysis.\n\nAnalysis:\n\nstatic int ets_qdisc_change(struct Qdisc *sch, struct nlattr *opt,\n                          struct netlink_ext_ack *extack)\n{\n...\n\n      // (1) this lock is preventing .change handler (`ets_qdisc_change`)\n      //to race with .dequeue handler (`ets_qdisc_dequeue`)\n      sch_tree_lock(sch);\n\n      for (i = nbands; i \u003c oldbands; i++) {\n              if (i \u003e= q-\u003enstrict \u0026\u0026 q-\u003eclasses[i].qdisc-\u003eq.qlen)\n                      list_del_init(\u0026q-\u003eclasses[i].alist);\n              qdisc_purge_queue(q-\u003eclasses[i].qdisc);\n      }\n\n      WRITE_ONCE(q-\u003enbands, nbands);\n      for (i = nstrict; i \u003c q-\u003enstrict; i++) {\n              if (q-\u003eclasses[i].qdisc-\u003eq.qlen) {\n\t\t      // (2) the class is added to the q-\u003eactive\n                      list_add_tail(\u0026q-\u003eclasses[i].alist, \u0026q-\u003eactive);\n                      q-\u003eclasses[i].deficit = quanta[i];\n              }\n      }\n      WRITE_ONCE(q-\u003enstrict, nstrict);\n      memcpy(q-\u003eprio2band, priomap, sizeof(priomap));\n\n      for (i = 0; i \u003c q-\u003enbands; i++)\n              WRITE_ONCE(q-\u003eclasses[i].quantum, quanta[i]);\n\n      for (i = oldbands; i \u003c q-\u003enbands; i++) {\n              q-\u003eclasses[i].qdisc = queues[i];\n              if (q-\u003eclasses[i].qdisc != \u0026noop_qdisc)\n                      qdisc_hash_add(q-\u003eclasses[i].qdisc, true);\n      }\n\n      // (3) the qdisc is unlocked, now dequeue can be called in parallel\n      // to the rest of .change handler\n      sch_tree_unlock(sch);\n\n      ets_offload_change(sch);\n      for (i = q-\u003enbands; i \u003c oldbands; i++) {\n\t      // (4) we\u0027re reducing the refcount for our class\u0027s qdisc and\n\t      //  freeing it\n              qdisc_put(q-\u003eclasses[i].qdisc);\n\t      // (5) If we call .dequeue between (4) and (5), we will have\n\t      // a strong UAF and we can control RIP\n              q-\u003eclasses[i].qdisc = NULL;\n              WRITE_ONCE(q-\u003eclasses[i].quantum, 0);\n              q-\u003eclasses[i].deficit = 0;\n              gnet_stats_basic_sync_init(\u0026q-\u003eclasses[i].bstats);\n              memset(\u0026q-\u003eclasses[i].qstats, 0, sizeof(q-\u003eclasses[i].qstats));\n      }\n      return 0;\n}\n\nComment:\nThis happens because some of the classes have their qdiscs assigned to\nNULL, but remain in the active list. This commit fixes this issue by always\nremoving the class from the active list before deleting and freeing its\nassociated qdisc\n\nReproducer Steps\n(trimmed version of what was sent by zdi-disclosures@trendmicro.com)\n\n```\nDEV=\"${DEV:-lo}\"\nROOT_HANDLE=\"${ROOT_HANDLE:-1:}\"\nBAND2_HANDLE=\"${BAND2_HANDLE:-20:}\"   # child under 1:2\nPING_BYTES=\"${PING_BYTES:-48}\"\nPING_COUNT=\"${PING_COUNT:-200000}\"\nPING_DST=\"${PING_DST:-127.0.0.1}\"\n\nSLOW_TBF_RATE=\"${SLOW_TBF_RATE:-8bit}\"\nSLOW_TBF_BURST=\"${SLOW_TBF_BURST:-100b}\"\nSLOW_TBF_LAT=\"${SLOW_TBF_LAT:-1s}\"\n\ncleanup() {\n  tc qdisc del dev \"$DEV\" root 2\u003e/dev/null\n}\ntrap cleanup EXIT\n\nip link set \"$DEV\" up\n\ntc qdisc del dev \"$DEV\" root 2\u003e/dev/null || true\n\ntc qdisc add dev \"$DEV\" root handle \"$ROOT_HANDLE\" ets bands 2 strict 2\n\ntc qdisc add dev \"$DEV\" parent 1:2 handle \"$BAND2_HANDLE\" \\\n  tbf rate \"$SLOW_TBF_RATE\" burst \"$SLOW_TBF_BURST\" latency \"$SLOW_TBF_LAT\"\n\ntc filter add dev \"$DEV\" parent 1: protocol all prio 1 u32 match u32 0 0 flowid 1:2\ntc -s qdisc ls dev $DEV\n\nping -I \"$DEV\" -f -c \"$PING_COUNT\" -s \"$PING_BYTES\" -W 0.001 \"$PING_DST\" \\\n  \u003e/dev/null 2\u003e\u00261 \u0026\ntc qdisc change dev \"$DEV\" root handle \"$ROOT_HANDLE\" ets bands 2 strict 0\ntc qdisc change dev \"$DEV\" root handle \"$ROOT_HANDLE\" ets bands 2 strict 2\ntc -s qdisc ls dev $DEV\ntc qdisc del dev \"$DEV\" parent \n---truncated---"
          },
          {
            "lang": "es",
            "value": "En el kernel de Linux, la siguiente vulnerabilidad ha sido resuelta:\n\nnet/sched: ets: Siempre eliminar la clase de la lista activa antes de eliminar en ets_qdisc_change\n\nzdi-disclosures@trendmicro.com dice:\n\nLa vulnerabilidad es una condici\u00f3n de carrera entre \u0027ets_qdisc_dequeue\u0027 y\n\u0027ets_qdisc_change\u0027. Conduce a UAF en el objeto \u0027struct Qdisc\u0027.\nEl atacante requiere la capacidad de crear un nuevo usuario y un espacio de nombres de red\npara activar el error.\nVer mi comentario adicional al final del an\u00e1lisis.\n\nAn\u00e1lisis:\n\nstatic int ets_qdisc_change(struct Qdisc *sch, struct nlattr *opt,\n                          struct netlink_ext_ack *extack)\n{\n...\n\n      // (1) este bloqueo est\u00e1 evitando que el manejador .change (\u0027ets_qdisc_change\u0027)\n      //compita con el manejador .dequeue (\u0027ets_qdisc_dequeue\u0027)\n      sch_tree_lock(sch);\n\n      for (i = nbands; i \u0026lt; oldbands; i++) {\n              if (i \u0026gt;= q-\u0026gt;nstrict \u0026amp;\u0026amp; q-\u0026gt;classes[i].qdisc-\u0026gt;q.qlen)\n                      list_del_init(\u0026amp;q-\u0026gt;classes[i].alist);\n              qdisc_purge_queue(q-\u0026gt;classes[i].qdisc);\n      }\n\n      WRITE_ONCE(q-\u0026gt;nbands, nbands);\n      for (i = nstrict; i \u0026lt; q-\u0026gt;nstrict; i++) {\n              if (q-\u0026gt;classes[i].qdisc-\u0026gt;q.qlen) {\n\t\t      // (2) la clase se a\u00f1ade a q-\u0026gt;active\n                      list_add_tail(\u0026amp;q-\u0026gt;classes[i].alist, \u0026amp;q-\u0026gt;active);\n                      q-\u0026gt;classes[i].deficit = quanta[i];\n              }\n      }\n      WRITE_ONCE(q-\u0026gt;nstrict, nstrict);\n      memcpy(q-\u0026gt;prio2band, priomap, sizeof(priomap));\n\n      for (i = 0; i \u0026lt; q-\u0026gt;nbands; i++)\n              WRITE_ONCE(q-\u0026gt;classes[i].quantum, quanta[i]);\n\n      for (i = oldbands; i \u0026lt; q-\u0026gt;nbands; i++) {\n              q-\u0026gt;classes[i].qdisc = queues[i];\n              if (q-\u0026gt;classes[i].qdisc != \u0026amp;noop_qdisc)\n                      qdisc_hash_add(q-\u0026gt;classes[i].qdisc, true);\n      }\n\n      // (3) el qdisc se desbloquea, ahora dequeue puede ser llamado en paralelo\n      // al resto del manejador .change\n      sch_tree_unlock(sch);\n\n      ets_offload_change(sch);\n      for (i = q-\u0026gt;nbands; i \u0026lt; oldbands; i++) {\n\t      // (4) estamos reduciendo el contador de referencias para el qdisc de nuestra clase y\n\t      //  liber\u00e1ndolo\n              qdisc_put(q-\u0026gt;classes[i].qdisc);\n\t      // (5) Si llamamos a .dequeue entre (4) y (5), tendremos\n\t      // un UAF fuerte y podremos controlar RIP\n              q-\u0026gt;classes[i].qdisc = NULL;\n              WRITE_ONCE(q-\u0026gt;classes[i].quantum, 0);\n              q-\u0026gt;classes[i].deficit = 0;\n              gnet_stats_basic_sync_init(\u0026amp;q-\u0026gt;classes[i].bstats);\n              memset(\u0026amp;q-\u0026gt;classes[i].qstats, 0, sizeof(q-\u0026gt;classes[i].qstats));\n      }\n      return 0;\n}\n\nComentario:\nEsto sucede porque algunas de las clases tienen sus qdiscs asignados a\nNULL, pero permanecen en la lista activa. Este commit soluciona este problema al siempre\neliminar la clase de la lista activa antes de eliminar y liberar su\nqdisc asociado.\n\nPasos para Reproducir\n(versi\u00f3n recortada de lo que fue enviado por zdi-disclosures@trendmicro.com)\n\n```\nDEV=\"${DEV:-lo}\"\nROOT_HANDLE=\"${ROOT_HANDLE:-1:}\"\nBAND2_HANDLE=\"${BAND2_HANDLE:-20:}\"   # child under 1:2\nPING_BYTES=\"${PING_BYTES:-48}\"\nPING_COUNT=\"${PING_COUNT:-200000}\"\nPING_DST=\"${PING_DST:-127.0.0.1}\"\n\nSLOW_TBF_RATE=\"${SLOW_TBF_RATE:-8bit}\"\nSLOW_TBF_BURST=\"${SLOW_TBF_BURST:-100b}\"\nSLOW_TBF_LAT=\"${SLOW_TBF_LAT:-1s}\"\n\ncleanup() {\n  tc qdisc del dev \"$DEV\" root 2\u0026gt;/dev/null\n}\ntrap cleanup EXIT\n\nip link set \"$DEV\" up\n\ntc qdisc del dev \"$DEV\" root 2\u0026gt;/dev/null || true\n\ntc qdisc add dev \"$DEV\" root handle \"$ROOT_HANDLE\" ets bands 2 strict 2\n\ntc qdisc add dev \"$DEV\" parent 1:2 handle \"$BAND2_HANDLE\" \\\n  tbf rate \"$SLOW_TBF_RATE\" burst \"$SLOW_TBF_BURST\" latency \"$SLOW_TBF_LAT\"\n\ntc filter add dev \"$DEV\" parent 1: protocol all prio 1 u32 match u32 0 0 flowid 1:2\ntc -s qdisc ls dev $DEV\n\nping -I \"$DEV\" -f -c \"$PING_COUNT\" -s \"$PING_BYTES\" -W 0.001 \"$PING_DST\" \\\n  \u0026gt;/dev/null 2\u0026gt;\u0026amp;1 \u0026amp;\ntc qdisc change dev \"$DEV\" root handle \"$ROOT_HANDLE\" ets bands 2 strict 0\nt"
          }
        ],
        "id": "CVE-2025-71066",
        "lastModified": "2026-07-30T06:24:47.800",
        "metrics": {
          "cvssMetricV31": [
            {
              "cvssData": {
                "attackComplexity": "LOW",
                "attackVector": "LOCAL",
                "availabilityImpact": "HIGH",
                "baseScore": 7.8,
                "baseSeverity": "HIGH",
                "confidentialityImpact": "HIGH",
                "integrityImpact": "HIGH",
                "privilegesRequired": "LOW",
                "scope": "UNCHANGED",
                "userInteraction": "NONE",
                "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
                "version": "3.1"
              },
              "exploitabilityScore": 1.8,
              "impactScore": 5.9,
              "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
              "type": "Secondary"
            },
            {
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                "attackComplexity": "HIGH",
                "attackVector": "LOCAL",
                "availabilityImpact": "HIGH",
                "baseScore": 7.5,
                "baseSeverity": "HIGH",
                "confidentialityImpact": "HIGH",
                "integrityImpact": "HIGH",
                "privilegesRequired": "HIGH",
                "scope": "CHANGED",
                "userInteraction": "NONE",
                "vectorString": "CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:C/C:H/I:H/A:H",
                "version": "3.1"
              },
              "exploitabilityScore": 0.8,
              "impactScore": 6.0,
              "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
              "type": "Secondary"
            }
          ],
          "ssvcV203": [
            {
              "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
              "ssvcData": {
                "id": "CVE-2025-71066",
                "options": [
                  {
                    "exploitation": "none"
                  },
                  {
                    "automatable": "no"
                  },
                  {
                    "technicalImpact": "total"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-05-22T03:55:51.470582Z",
                "version": "2.0.3"
              }
            }
          ]
        },
        "published": "2026-01-13T16:16:05.960",
        "references": [
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "url": "https://git.kernel.org/stable/c/062d5d544e564473450d72e6af83077c2b2ff7c3"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "url": "https://git.kernel.org/stable/c/06bfb66a7c8b45e3fed01351a4b087410ae5ef39"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "url": "https://git.kernel.org/stable/c/45466141da3c98a0c5fa88be0bc14b4b6a4bd75c"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "url": "https://git.kernel.org/stable/c/9987cda315c08f63a02423fa2f9a1f6602c861a0"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "url": "https://git.kernel.org/stable/c/a75d617a4ef08682f5cfaadc01d5141c87e019c9"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "url": "https://git.kernel.org/stable/c/c7f6e7cc14df72b997258216e99d897d2df0dbbd"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "url": "https://git.kernel.org/stable/c/ce052b9402e461a9aded599f5b47e76bc727f7de"
          }
        ],
        "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "vulnStatus": "Deferred",
        "weaknesses": [
          {
            "description": [
              {
                "lang": "en",
                "value": "CWE-362"
              }
            ],
            "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
            "type": "Secondary"
          }
        ]
      }
    },
    "redhat_vex": {
      "aggregate_severity": "Moderate",
      "current_release_date": "2026-07-30T08:33:24+00:00",
      "cve": "CVE-2025-71066",
      "id": "CVE-2025-71066",
      "initial_release_date": "2025-01-01T00:00:00+00:00",
      "product_status:fixed": "762",
      "product_status:known_affected": "22",
      "product_status:known_not_affected": "42",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: net/sched: ets: Always remove class from active list before deleting in ets_qdisc_change",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2025/cve-2025-71066.json",
      "version": "3"
    },
    "suse_vex": {
      "aggregate_severity": "important",
      "current_release_date": "2026-09-11T01:48:27Z",
      "cve": "CVE-2025-71066",
      "id": "CVE-2025-71066",
      "initial_release_date": "2026-01-14T00:26:05Z",
      "product_status:first_fixed": "2",
      "product_status:known_affected": "403",
      "product_status:known_not_affected": "177",
      "product_status:recommended": "792",
      "source": "SUSE CSAF VEX",
      "status": "interim",
      "title": "SUSE CVE CVE-2025-71066",
      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2025-71066.json",
      "version": "46"
    },
    "vulnrichment": {
      "containers": {
        "adp": [
          {
            "metrics": [
              {
                "cvssV3_1": {
                  "attackComplexity": "HIGH",
                  "attackVector": "LOCAL",
                  "availabilityImpact": "HIGH",
                  "baseScore": 7.5,
                  "baseSeverity": "HIGH",
                  "confidentialityImpact": "HIGH",
                  "integrityImpact": "HIGH",
                  "privilegesRequired": "HIGH",
                  "scope": "CHANGED",
                  "userInteraction": "NONE",
                  "vectorString": "CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:C/C:H/I:H/A:H",
                  "version": "3.1"
                }
              },
              {
                "other": {
                  "content": {
                    "id": "CVE-2025-71066",
                    "options": [
                      {
                        "Exploitation": "none"
                      },
                      {
                        "Automatable": "no"
                      },
                      {
                        "Technical Impact": "total"
                      }
                    ],
                    "role": "CISA Coordinator",
                    "timestamp": "2026-05-22T03:55:51.470582Z",
                    "version": "2.0.3"
                  },
                  "type": "ssvc"
                }
              }
            ],
            "problemTypes": [
              {
                "descriptions": [
                  {
                    "cweId": "CWE-362",
                    "description": "CWE-362 Concurrent Execution using Shared Resource with Improper Synchronization (\u0027Race Condition\u0027)",
                    "lang": "en",
                    "type": "CWE"
                  }
                ]
              }
            ],
            "providerMetadata": {
              "dateUpdated": "2026-05-22T12:50:05.426Z",
              "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
              "shortName": "CISA-ADP"
            },
            "title": "CISA ADP Vulnrichment"
          }
        ],
        "cna": {
          "affected": [
            {
              "defaultStatus": "unaffected",
              "product": "Linux",
              "programFiles": [
                "net/sched/sch_ets.c"
              ],
              "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
              "vendor": "Linux",
              "versions": [
                {
                  "lessThan": "062d5d544e564473450d72e6af83077c2b2ff7c3",
                  "status": "affected",
                  "version": "ae2659d2c670252759ee9c823c4e039c0e05a6f2",
                  "versionType": "git"
                },
                {
                  "lessThan": "c7f6e7cc14df72b997258216e99d897d2df0dbbd",
                  "status": "affected",
                  "version": "e25bdbc7e951ae5728fee1f4c09485df113d013c",
                  "versionType": "git"
                },
                {
                  "lessThan": "a75d617a4ef08682f5cfaadc01d5141c87e019c9",
                  "status": "affected",
                  "version": "de6d25924c2a8c2988c6a385990cafbe742061bf",
                  "versionType": "git"
                },
                {
                  "lessThan": "9987cda315c08f63a02423fa2f9a1f6602c861a0",
                  "status": "affected",
                  "version": "de6d25924c2a8c2988c6a385990cafbe742061bf",
                  "versionType": "git"
                },
                {
                  "lessThan": "06bfb66a7c8b45e3fed01351a4b087410ae5ef39",
                  "status": "affected",
                  "version": "de6d25924c2a8c2988c6a385990cafbe742061bf",
                  "versionType": "git"
                },
                {
                  "lessThan": "45466141da3c98a0c5fa88be0bc14b4b6a4bd75c",
                  "status": "affected",
                  "version": "de6d25924c2a8c2988c6a385990cafbe742061bf",
                  "versionType": "git"
                },
                {
                  "lessThan": "ce052b9402e461a9aded599f5b47e76bc727f7de",
                  "status": "affected",
                  "version": "de6d25924c2a8c2988c6a385990cafbe742061bf",
                  "versionType": "git"
                }
              ]
            },
            {
              "defaultStatus": "affected",
              "product": "Linux",
              "programFiles": [
                "net/sched/sch_ets.c"
              ],
              "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
              "vendor": "Linux",
              "versions": [
                {
                  "status": "affected",
                  "version": "5.16"
                },
                {
                  "lessThan": "5.16",
                  "status": "unaffected",
                  "version": "0",
                  "versionType": "semver"
                },
                {
                  "lessThanOrEqual": "5.10.*",
                  "status": "unaffected",
                  "version": "5.10.248",
                  "versionType": "semver"
                },
                {
                  "lessThanOrEqual": "5.15.*",
                  "status": "unaffected",
                  "version": "5.15.198",
                  "versionType": "semver"
                },
                {
                  "lessThanOrEqual": "6.1.*",
                  "status": "unaffected",
                  "version": "6.1.160",
                  "versionType": "semver"
                },
                {
                  "lessThanOrEqual": "6.6.*",
                  "status": "unaffected",
                  "version": "6.6.120",
                  "versionType": "semver"
                },
                {
                  "lessThanOrEqual": "6.12.*",
                  "status": "unaffected",
                  "version": "6.12.64",
                  "versionType": "semver"
                },
                {
                  "lessThanOrEqual": "6.18.*",
                  "status": "unaffected",
                  "version": "6.18.3",
                  "versionType": "semver"
                },
                {
                  "lessThanOrEqual": "*",
                  "status": "unaffected",
                  "version": "6.19",
                  "versionType": "original_commit_for_fix"
                }
              ]
            }
          ],
          "cpeApplicability": [
            {
              "nodes": [
                {
                  "cpeMatch": [
                    {
                      "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                      "versionEndExcluding": "5.10.248",
                      "versionStartIncluding": "5.10.83",
                      "vulnerable": true
                    },
                    {
                      "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                      "versionEndExcluding": "5.15.198",
                      "versionStartIncluding": "5.15.6",
                      "vulnerable": true
                    },
                    {
                      "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                      "versionEndExcluding": "6.1.160",
                      "versionStartIncluding": "5.16",
                      "vulnerable": true
                    },
                    {
                      "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                      "versionEndExcluding": "6.6.120",
                      "versionStartIncluding": "5.16",
                      "vulnerable": true
                    },
                    {
                      "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                      "versionEndExcluding": "6.12.64",
                      "versionStartIncluding": "5.16",
                      "vulnerable": true
                    },
                    {
                      "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                      "versionEndExcluding": "6.18.3",
                      "versionStartIncluding": "5.16",
                      "vulnerable": true
                    },
                    {
                      "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                      "versionEndExcluding": "6.19",
                      "versionStartIncluding": "5.16",
                      "vulnerable": true
                    }
                  ],
                  "negate": false,
                  "operator": "OR"
                }
              ]
            }
          ],
          "descriptions": [
            {
              "lang": "en",
              "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: ets: Always remove class from active list before deleting in ets_qdisc_change\n\nzdi-disclosures@trendmicro.com says:\n\nThe vulnerability is a race condition between `ets_qdisc_dequeue` and\n`ets_qdisc_change`.  It leads to UAF on `struct Qdisc` object.\nAttacker requires the capability to create new user and network namespace\nin order to trigger the bug.\nSee my additional commentary at the end of the analysis.\n\nAnalysis:\n\nstatic int ets_qdisc_change(struct Qdisc *sch, struct nlattr *opt,\n                          struct netlink_ext_ack *extack)\n{\n...\n\n      // (1) this lock is preventing .change handler (`ets_qdisc_change`)\n      //to race with .dequeue handler (`ets_qdisc_dequeue`)\n      sch_tree_lock(sch);\n\n      for (i = nbands; i \u003c oldbands; i++) {\n              if (i \u003e= q-\u003enstrict \u0026\u0026 q-\u003eclasses[i].qdisc-\u003eq.qlen)\n                      list_del_init(\u0026q-\u003eclasses[i].alist);\n              qdisc_purge_queue(q-\u003eclasses[i].qdisc);\n      }\n\n      WRITE_ONCE(q-\u003enbands, nbands);\n      for (i = nstrict; i \u003c q-\u003enstrict; i++) {\n              if (q-\u003eclasses[i].qdisc-\u003eq.qlen) {\n\t\t      // (2) the class is added to the q-\u003eactive\n                      list_add_tail(\u0026q-\u003eclasses[i].alist, \u0026q-\u003eactive);\n                      q-\u003eclasses[i].deficit = quanta[i];\n              }\n      }\n      WRITE_ONCE(q-\u003enstrict, nstrict);\n      memcpy(q-\u003eprio2band, priomap, sizeof(priomap));\n\n      for (i = 0; i \u003c q-\u003enbands; i++)\n              WRITE_ONCE(q-\u003eclasses[i].quantum, quanta[i]);\n\n      for (i = oldbands; i \u003c q-\u003enbands; i++) {\n              q-\u003eclasses[i].qdisc = queues[i];\n              if (q-\u003eclasses[i].qdisc != \u0026noop_qdisc)\n                      qdisc_hash_add(q-\u003eclasses[i].qdisc, true);\n      }\n\n      // (3) the qdisc is unlocked, now dequeue can be called in parallel\n      // to the rest of .change handler\n      sch_tree_unlock(sch);\n\n      ets_offload_change(sch);\n      for (i = q-\u003enbands; i \u003c oldbands; i++) {\n\t      // (4) we\u0027re reducing the refcount for our class\u0027s qdisc and\n\t      //  freeing it\n              qdisc_put(q-\u003eclasses[i].qdisc);\n\t      // (5) If we call .dequeue between (4) and (5), we will have\n\t      // a strong UAF and we can control RIP\n              q-\u003eclasses[i].qdisc = NULL;\n              WRITE_ONCE(q-\u003eclasses[i].quantum, 0);\n              q-\u003eclasses[i].deficit = 0;\n              gnet_stats_basic_sync_init(\u0026q-\u003eclasses[i].bstats);\n              memset(\u0026q-\u003eclasses[i].qstats, 0, sizeof(q-\u003eclasses[i].qstats));\n      }\n      return 0;\n}\n\nComment:\nThis happens because some of the classes have their qdiscs assigned to\nNULL, but remain in the active list. This commit fixes this issue by always\nremoving the class from the active list before deleting and freeing its\nassociated qdisc\n\nReproducer Steps\n(trimmed version of what was sent by zdi-disclosures@trendmicro.com)\n\n```\nDEV=\"${DEV:-lo}\"\nROOT_HANDLE=\"${ROOT_HANDLE:-1:}\"\nBAND2_HANDLE=\"${BAND2_HANDLE:-20:}\"   # child under 1:2\nPING_BYTES=\"${PING_BYTES:-48}\"\nPING_COUNT=\"${PING_COUNT:-200000}\"\nPING_DST=\"${PING_DST:-127.0.0.1}\"\n\nSLOW_TBF_RATE=\"${SLOW_TBF_RATE:-8bit}\"\nSLOW_TBF_BURST=\"${SLOW_TBF_BURST:-100b}\"\nSLOW_TBF_LAT=\"${SLOW_TBF_LAT:-1s}\"\n\ncleanup() {\n  tc qdisc del dev \"$DEV\" root 2\u003e/dev/null\n}\ntrap cleanup EXIT\n\nip link set \"$DEV\" up\n\ntc qdisc del dev \"$DEV\" root 2\u003e/dev/null || true\n\ntc qdisc add dev \"$DEV\" root handle \"$ROOT_HANDLE\" ets bands 2 strict 2\n\ntc qdisc add dev \"$DEV\" parent 1:2 handle \"$BAND2_HANDLE\" \\\n  tbf rate \"$SLOW_TBF_RATE\" burst \"$SLOW_TBF_BURST\" latency \"$SLOW_TBF_LAT\"\n\ntc filter add dev \"$DEV\" parent 1: protocol all prio 1 u32 match u32 0 0 flowid 1:2\ntc -s qdisc ls dev $DEV\n\nping -I \"$DEV\" -f -c \"$PING_COUNT\" -s \"$PING_BYTES\" -W 0.001 \"$PING_DST\" \\\n  \u003e/dev/null 2\u003e\u00261 \u0026\ntc qdisc change dev \"$DEV\" root handle \"$ROOT_HANDLE\" ets bands 2 strict 0\ntc qdisc change dev \"$DEV\" root handle \"$ROOT_HANDLE\" ets bands 2 strict 2\ntc -s qdisc ls dev $DEV\ntc qdisc del dev \"$DEV\" parent \n---truncated---"
            }
          ],
          "providerMetadata": {
            "dateUpdated": "2026-05-11T21:54:04.683Z",
            "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "shortName": "Linux"
          },
          "references": [
            {
              "url": "https://git.kernel.org/stable/c/062d5d544e564473450d72e6af83077c2b2ff7c3"
            },
            {
              "url": "https://git.kernel.org/stable/c/c7f6e7cc14df72b997258216e99d897d2df0dbbd"
            },
            {
              "url": "https://git.kernel.org/stable/c/a75d617a4ef08682f5cfaadc01d5141c87e019c9"
            },
            {
              "url": "https://git.kernel.org/stable/c/9987cda315c08f63a02423fa2f9a1f6602c861a0"
            },
            {
              "url": "https://git.kernel.org/stable/c/06bfb66a7c8b45e3fed01351a4b087410ae5ef39"
            },
            {
              "url": "https://git.kernel.org/stable/c/45466141da3c98a0c5fa88be0bc14b4b6a4bd75c"
            },
            {
              "url": "https://git.kernel.org/stable/c/ce052b9402e461a9aded599f5b47e76bc727f7de"
            }
          ],
          "title": "net/sched: ets: Always remove class from active list before deleting in ets_qdisc_change",
          "x_generator": {
            "engine": "bippy-1.2.0"
          }
        }
      },
      "cveMetadata": {
        "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "assignerShortName": "Linux",
        "cveId": "CVE-2025-71066",
        "datePublished": "2026-01-13T15:31:21.931Z",
        "dateReserved": "2026-01-13T15:30:19.646Z",
        "dateUpdated": "2026-05-22T12:50:15.711Z",
        "state": "PUBLISHED"
      },
      "dataType": "CVE_RECORD",
      "dataVersion": "5.2"
    }
  }
}



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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.


Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.