CVE-2026-74427 (GCVE-0-2026-74427)

Vulnerability from cvelistv5 – Published: 2026-08-15 05:59 – Updated: 2026-08-17 05:47
VLAI
Title
afs: Fix netns teardown to cancel the preallocation charger
Summary
In the Linux kernel, the following vulnerability has been resolved: afs: Fix netns teardown to cancel the preallocation charger Fix the teardown of an afs network namespace to make sure it cancels the work item that keeps the preallocated rxrpc call/conn/peer queue charged before incoming calls are disabled (i.e. listen 0). Also, if net->live is false because the afs netns is being deleted, make afs_charge_preallocation() skip charging and make afs_rx_new_call() avoid requeuing the charger. (This was found by AI review).
Severity
9.8 (Critical)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: 00e907127e6f86d0f9b122d9b4347a8aa09a8b61 , < 63ccaf1bdf8be2330f47f9b5b233dd3fd04acbd9 (git)
Affected: 00e907127e6f86d0f9b122d9b4347a8aa09a8b61 , < f5096e18b6b7fbd1c2a1942e275a51bcfdfb2ad1 (git)
Affected: 00e907127e6f86d0f9b122d9b4347a8aa09a8b61 , < 59e8b7652f6cbfb62d377ead0ad553c1b4e39a7a (git)
Affected: 00e907127e6f86d0f9b122d9b4347a8aa09a8b61 , < 85d5fb80fe4f0cc836b6df83f26de204fe102ff7 (git)
Affected: 00e907127e6f86d0f9b122d9b4347a8aa09a8b61 , < a33975ff2b6ea47b8f29956403374b1cdd057539 (git)
Affected: 00e907127e6f86d0f9b122d9b4347a8aa09a8b61 , < b83ecf80e28afb7b6595ba79932e77ca68a5a83d (git)
Affected: 00e907127e6f86d0f9b122d9b4347a8aa09a8b61 , < eec89c5f8e1adc1de4824042ef75f62aed804153 (git)
Affected: 00e907127e6f86d0f9b122d9b4347a8aa09a8b61 , < 47694fbc9d24ab6bf210f91e8efe06a10a478064 (git)
guessed Create a notification for this product.
Linux Linux Affected: 4.9
Unaffected: 0 , < 4.9 (semver)
Unaffected: 5.10.261 , ≤ 5.10.* (semver)
Unaffected: 5.15.212 , ≤ 5.15.* (semver)
Unaffected: 6.1.178 , ≤ 6.1.* (semver)
Unaffected: 6.6.145 , ≤ 6.6.* (semver)
Unaffected: 6.12.97 , ≤ 6.12.* (semver)
Unaffected: 6.18.40 , ≤ 6.18.* (semver)
Unaffected: 7.1.5 , ≤ 7.1.* (semver)
Unaffected: 7.2 , ≤ * (original_commit_for_fix)
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "fs/afs/rxrpc.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "63ccaf1bdf8be2330f47f9b5b233dd3fd04acbd9",
              "status": "affected",
              "version": "00e907127e6f86d0f9b122d9b4347a8aa09a8b61",
              "versionType": "git"
            },
            {
              "lessThan": "f5096e18b6b7fbd1c2a1942e275a51bcfdfb2ad1",
              "status": "affected",
              "version": "00e907127e6f86d0f9b122d9b4347a8aa09a8b61",
              "versionType": "git"
            },
            {
              "lessThan": "59e8b7652f6cbfb62d377ead0ad553c1b4e39a7a",
              "status": "affected",
              "version": "00e907127e6f86d0f9b122d9b4347a8aa09a8b61",
              "versionType": "git"
            },
            {
              "lessThan": "85d5fb80fe4f0cc836b6df83f26de204fe102ff7",
              "status": "affected",
              "version": "00e907127e6f86d0f9b122d9b4347a8aa09a8b61",
              "versionType": "git"
            },
            {
              "lessThan": "a33975ff2b6ea47b8f29956403374b1cdd057539",
              "status": "affected",
              "version": "00e907127e6f86d0f9b122d9b4347a8aa09a8b61",
              "versionType": "git"
            },
            {
              "lessThan": "b83ecf80e28afb7b6595ba79932e77ca68a5a83d",
              "status": "affected",
              "version": "00e907127e6f86d0f9b122d9b4347a8aa09a8b61",
              "versionType": "git"
            },
            {
              "lessThan": "eec89c5f8e1adc1de4824042ef75f62aed804153",
              "status": "affected",
              "version": "00e907127e6f86d0f9b122d9b4347a8aa09a8b61",
              "versionType": "git"
            },
            {
              "lessThan": "47694fbc9d24ab6bf210f91e8efe06a10a478064",
              "status": "affected",
              "version": "00e907127e6f86d0f9b122d9b4347a8aa09a8b61",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "fs/afs/rxrpc.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "4.9"
            },
            {
              "lessThan": "4.9",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.10.*",
              "status": "unaffected",
              "version": "5.10.261",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.15.*",
              "status": "unaffected",
              "version": "5.15.212",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.1.*",
              "status": "unaffected",
              "version": "6.1.178",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.145",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.97",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.40",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.1.*",
              "status": "unaffected",
              "version": "7.1.5",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.2",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "5.10.261",
                  "versionStartIncluding": "4.9",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "5.15.212",
                  "versionStartIncluding": "4.9",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.1.178",
                  "versionStartIncluding": "4.9",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.6.145",
                  "versionStartIncluding": "4.9",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.12.97",
                  "versionStartIncluding": "4.9",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.18.40",
                  "versionStartIncluding": "4.9",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.1.5",
                  "versionStartIncluding": "4.9",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.2",
                  "versionStartIncluding": "4.9",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nafs: Fix netns teardown to cancel the preallocation charger\n\nFix the teardown of an afs network namespace to make sure it cancels the\nwork item that keeps the preallocated rxrpc call/conn/peer queue charged\nbefore incoming calls are disabled (i.e. listen 0).\n\nAlso, if net-\u003elive is false because the afs netns is being deleted, make\nafs_charge_preallocation() skip charging and make afs_rx_new_call() avoid\nrequeuing the charger.\n\n(This was found by AI review)."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "baseScore": 9.8,
            "baseSeverity": "CRITICAL",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
            "version": "3.1"
          },
          "scenarios": [
            {
              "lang": "en",
              "value": "AV:N - Remote RxRPC/UDP traffic to the kafs callback manager on port 7001 reaches afs_rx_new_call through rxrpc incoming-call processing and can requeue charge_preallocation_work that touches per-net AFS state during namespace teardown, matching other network-reachable netns-teardown UAF bugs.\nAC:L - The attacker controls both sides of the race\u2014namespace create/destroy timing via user namespaces or container lifecycle, plus concurrent RxRPC callback floods\u2014and the follow-up fix confirms incoming I/O-thread calls can requeue the charger after listen(0); the window is wide and repeatable.\nPR:N - afs_rx_new_call is invoked during RXRPC_CONN_SERVICE_CHALLENGING before AFS credential verification completes, so a remote peer sending valid CM-service RxRPC DATA can drive the bug; alternatively an unprivileged user obtains CAP_NET_ADMIN via user namespaces to destroy the namespace.\nUI:N - No victim interaction such as mounting AFS volumes or opening files is required; exploitation relies on attacker-driven namespace teardown and/or RxRPC packets, both kernel-level events under attacker or infrastructure control.\nS:U - The UAF corrupts kernel heap objects within the same OS security authority; impact does not cross a VM, IOMMU, or KVM/Xen boundary into a separate security domain.\nC:H - charge_preallocation_work on afs_wq dereferences freed struct afs_net fields (socket, spare_incoming_call, nr_outstanding_calls) after per-net exit; UAF of slab objects enables arbitrary kernel memory disclosure via heap grooming.\nI:H - Continued charging and afs_alloc_call through freed afs_net writes into stale per-net counters and socket state; UAF supports heap spray and arbitrary kernel write or control-flow hijack primitives.\nA:H - Use-after-free on afs_net and its RxRPC socket during teardown causes kernel oops or panic; even without full exploitation the race reliably crashes the host and can be retriggered on demand."
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-17T05:47:02.011Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/63ccaf1bdf8be2330f47f9b5b233dd3fd04acbd9"
        },
        {
          "url": "https://git.kernel.org/stable/c/f5096e18b6b7fbd1c2a1942e275a51bcfdfb2ad1"
        },
        {
          "url": "https://git.kernel.org/stable/c/59e8b7652f6cbfb62d377ead0ad553c1b4e39a7a"
        },
        {
          "url": "https://git.kernel.org/stable/c/85d5fb80fe4f0cc836b6df83f26de204fe102ff7"
        },
        {
          "url": "https://git.kernel.org/stable/c/a33975ff2b6ea47b8f29956403374b1cdd057539"
        },
        {
          "url": "https://git.kernel.org/stable/c/b83ecf80e28afb7b6595ba79932e77ca68a5a83d"
        },
        {
          "url": "https://git.kernel.org/stable/c/eec89c5f8e1adc1de4824042ef75f62aed804153"
        },
        {
          "url": "https://git.kernel.org/stable/c/47694fbc9d24ab6bf210f91e8efe06a10a478064"
        }
      ],
      "title": "afs: Fix netns teardown to cancel the preallocation charger",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-74427",
    "datePublished": "2026-08-15T05:59:29.053Z",
    "dateReserved": "2026-08-15T05:44:03.895Z",
    "dateUpdated": "2026-08-17T05:47:02.011Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2026-74427",
      "date": "2026-08-21",
      "epss": "0.00404",
      "percentile": "0.33907"
    },
    "nvd": "{\"cve\":{\"id\":\"CVE-2026-74427\",\"sourceIdentifier\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"published\":\"2026-08-15T06:22:44.810\",\"lastModified\":\"2026-08-17T06:19:38.237\",\"vulnStatus\":\"Received\",\"cveTags\":[],\"descriptions\":[{\"lang\":\"en\",\"value\":\"In the Linux kernel, the following vulnerability has been resolved:\\n\\nafs: Fix netns teardown to cancel the preallocation charger\\n\\nFix the teardown of an afs network namespace to make sure it cancels the\\nwork item that keeps the preallocated rxrpc call/conn/peer queue charged\\nbefore incoming calls are disabled (i.e. listen 0).\\n\\nAlso, if net-\u003elive is false because the afs netns is being deleted, make\\nafs_charge_preallocation() skip charging and make afs_rx_new_call() avoid\\nrequeuing the charger.\\n\\n(This was found by AI review).\"}],\"affected\":[{\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"affectedData\":[{\"vendor\":\"Linux\",\"product\":\"Linux\",\"defaultStatus\":\"unaffected\",\"programFiles\":[\"fs/afs/rxrpc.c\"],\"repo\":\"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\"versions\":[{\"version\":\"00e907127e6f86d0f9b122d9b4347a8aa09a8b61\",\"lessThan\":\"63ccaf1bdf8be2330f47f9b5b233dd3fd04acbd9\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"00e907127e6f86d0f9b122d9b4347a8aa09a8b61\",\"lessThan\":\"f5096e18b6b7fbd1c2a1942e275a51bcfdfb2ad1\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"00e907127e6f86d0f9b122d9b4347a8aa09a8b61\",\"lessThan\":\"59e8b7652f6cbfb62d377ead0ad553c1b4e39a7a\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"00e907127e6f86d0f9b122d9b4347a8aa09a8b61\",\"lessThan\":\"85d5fb80fe4f0cc836b6df83f26de204fe102ff7\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"00e907127e6f86d0f9b122d9b4347a8aa09a8b61\",\"lessThan\":\"a33975ff2b6ea47b8f29956403374b1cdd057539\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"00e907127e6f86d0f9b122d9b4347a8aa09a8b61\",\"lessThan\":\"b83ecf80e28afb7b6595ba79932e77ca68a5a83d\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"00e907127e6f86d0f9b122d9b4347a8aa09a8b61\",\"lessThan\":\"eec89c5f8e1adc1de4824042ef75f62aed804153\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"00e907127e6f86d0f9b122d9b4347a8aa09a8b61\",\"lessThan\":\"47694fbc9d24ab6bf210f91e8efe06a10a478064\",\"versionType\":\"git\",\"status\":\"affected\"}]},{\"vendor\":\"Linux\",\"product\":\"Linux\",\"defaultStatus\":\"affected\",\"programFiles\":[\"fs/afs/rxrpc.c\"],\"repo\":\"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\"versions\":[{\"version\":\"4.9\",\"status\":\"affected\"},{\"version\":\"0\",\"lessThan\":\"4.9\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"5.10.261\",\"lessThanOrEqual\":\"5.10.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"5.15.212\",\"lessThanOrEqual\":\"5.15.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.1.178\",\"lessThanOrEqual\":\"6.1.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.6.145\",\"lessThanOrEqual\":\"6.6.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.12.97\",\"lessThanOrEqual\":\"6.12.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.18.40\",\"lessThanOrEqual\":\"6.18.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"7.1.5\",\"lessThanOrEqual\":\"7.1.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"7.2\",\"lessThanOrEqual\":\"*\",\"versionType\":\"original_commit_for_fix\",\"status\":\"unaffected\"}]}]}],\"metrics\":{\"cvssMetricV31\":[{\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"type\":\"Secondary\",\"cvssData\":{\"version\":\"3.1\",\"vectorString\":\"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H\",\"baseScore\":9.8,\"baseSeverity\":\"CRITICAL\",\"attackVector\":\"NETWORK\",\"attackComplexity\":\"LOW\",\"privilegesRequired\":\"NONE\",\"userInteraction\":\"NONE\",\"scope\":\"UNCHANGED\",\"confidentialityImpact\":\"HIGH\",\"integrityImpact\":\"HIGH\",\"availabilityImpact\":\"HIGH\"},\"exploitabilityScore\":3.9,\"impactScore\":5.9}]},\"references\":[{\"url\":\"https://git.kernel.org/stable/c/47694fbc9d24ab6bf210f91e8efe06a10a478064\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/59e8b7652f6cbfb62d377ead0ad553c1b4e39a7a\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/63ccaf1bdf8be2330f47f9b5b233dd3fd04acbd9\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/85d5fb80fe4f0cc836b6df83f26de204fe102ff7\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/a33975ff2b6ea47b8f29956403374b1cdd057539\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/b83ecf80e28afb7b6595ba79932e77ca68a5a83d\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/eec89c5f8e1adc1de4824042ef75f62aed804153\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/f5096e18b6b7fbd1c2a1942e275a51bcfdfb2ad1\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"}]}}",
    "redhat_vex": {
      "aggregate_severity": "Moderate",
      "current_release_date": "2026-08-19T10:00:52+00:00",
      "cve": "CVE-2026-74427",
      "id": "CVE-2026-74427",
      "initial_release_date": "2026-08-15T00:00:00+00:00",
      "product_status:known_affected": "184",
      "product_status:known_not_affected": "90",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: afs: Fix netns teardown to cancel the preallocation charger",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-74427.json",
      "version": "3"
    }
  }
}



Log in or create an account to share your comment.




Tags
Taxonomy of the tags.





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

Author Source Type Date Other

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.