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CVE-2025-39703 (GCVE-0-2025-39703)

Vulnerability from cvelistv5 – Published: 2025-09-05 17:21 – Updated: 2026-08-05 12:04
VLAI
Title
net, hsr: reject HSR frame if skb can't hold tag
Summary
In the Linux kernel, the following vulnerability has been resolved: net, hsr: reject HSR frame if skb can't hold tag Receiving HSR frame with insufficient space to hold HSR tag in the skb can result in a crash (kernel BUG): [ 45.390915] skbuff: skb_under_panic: text:ffffffff86f32cac len:26 put:14 head:ffff888042418000 data:ffff888042417ff4 tail:0xe end:0x180 dev:bridge_slave_1 [ 45.392559] ------------[ cut here ]------------ [ 45.392912] kernel BUG at net/core/skbuff.c:211! [ 45.393276] Oops: invalid opcode: 0000 [#1] SMP DEBUG_PAGEALLOC KASAN NOPTI [ 45.393809] CPU: 1 UID: 0 PID: 2496 Comm: reproducer Not tainted 6.15.0 #12 PREEMPT(undef) [ 45.394433] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014 [ 45.395273] RIP: 0010:skb_panic+0x15b/0x1d0 <snip registers, remove unreliable trace> [ 45.402911] Call Trace: [ 45.403105] <IRQ> [ 45.404470] skb_push+0xcd/0xf0 [ 45.404726] br_dev_queue_push_xmit+0x7c/0x6c0 [ 45.406513] br_forward_finish+0x128/0x260 [ 45.408483] __br_forward+0x42d/0x590 [ 45.409464] maybe_deliver+0x2eb/0x420 [ 45.409763] br_flood+0x174/0x4a0 [ 45.410030] br_handle_frame_finish+0xc7c/0x1bc0 [ 45.411618] br_handle_frame+0xac3/0x1230 [ 45.413674] __netif_receive_skb_core.constprop.0+0x808/0x3df0 [ 45.422966] __netif_receive_skb_one_core+0xb4/0x1f0 [ 45.424478] __netif_receive_skb+0x22/0x170 [ 45.424806] process_backlog+0x242/0x6d0 [ 45.425116] __napi_poll+0xbb/0x630 [ 45.425394] net_rx_action+0x4d1/0xcc0 [ 45.427613] handle_softirqs+0x1a4/0x580 [ 45.427926] do_softirq+0x74/0x90 [ 45.428196] </IRQ> This issue was found by syzkaller. The panic happens in br_dev_queue_push_xmit() once it receives a corrupted skb with ETH header already pushed in linear data. When it attempts the skb_push() call, there's not enough headroom and skb_push() panics. The corrupted skb is put on the queue by HSR layer, which makes a sequence of unintended transformations when it receives a specific corrupted HSR frame (with incomplete TAG). Fix it by dropping and consuming frames that are not long enough to contain both ethernet and hsr headers. Alternative fix would be to check for enough headroom before skb_push() in br_dev_queue_push_xmit(). In the reproducer, this is injected via AF_PACKET, but I don't easily see why it couldn't be sent over the wire from adjacent network. Further Details: In the reproducer, the following network interface chain is set up: ┌────────────────┐ ┌────────────────┐ │ veth0_to_hsr ├───┤ hsr_slave0 ┼───┐ └────────────────┘ └────────────────┘ │ │ ┌──────┐ ├─┤ hsr0 ├───┐ │ └──────┘ │ ┌────────────────┐ ┌────────────────┐ │ │┌────────┐ │ veth1_to_hsr ┼───┤ hsr_slave1 ├───┘ └┤ │ └────────────────┘ └────────────────┘ ┌┼ bridge │ ││ │ │└────────┘ │ ┌───────┐ │ │ ... ├──────┘ └───────┘ To trigger the events leading up to crash, reproducer sends a corrupted HSR fr ---truncated---
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: f6442ee08fe66c8e45c4f246531a2aaf4f17a7a7 , < 8d9bc4a375a1ba05f7dfa0407de8e510ab9bd14d (git)
Affected: 48b491a5cc74333c4a6a82fe21cea42c055a3b0b , < 3ae272ab523dd6bdc26e879027ed79feac9dd1b3 (git)
Affected: 48b491a5cc74333c4a6a82fe21cea42c055a3b0b , < b640188b8a6690e685939053c7efdbc7818b5f4e (git)
Affected: 48b491a5cc74333c4a6a82fe21cea42c055a3b0b , < b117c41b00902c1a7e24347c405cb82504aeae0b (git)
Affected: 48b491a5cc74333c4a6a82fe21cea42c055a3b0b , < acd69b597bd3f76d3b3d322b84082226c00eeaa4 (git)
Affected: 48b491a5cc74333c4a6a82fe21cea42c055a3b0b , < 61009439e4bd8d74e705ee15940760321be91d8a (git)
Affected: 48b491a5cc74333c4a6a82fe21cea42c055a3b0b , < 7af76e9d18a9fd6f8611b3313c86c190f9b6a5a7 (git)
Affected: 4ffd1d4a6b306ff69cbe412d2c54d2dd349ff436 (git)
Affected: 5.10.42 , < 5.10.241 (semver)
Affected: 5.12.9 , < 5.13 (semver)
guessed Create a notification for this product.
Linux Linux Affected: 5.13
Unaffected: 0 , < 5.13 (semver)
Unaffected: 5.10.241 , ≤ 5.10.* (semver)
Unaffected: 5.15.190 , ≤ 5.15.* (semver)
Unaffected: 6.1.149 , ≤ 6.1.* (semver)
Unaffected: 6.6.103 , ≤ 6.6.* (semver)
Unaffected: 6.12.44 , ≤ 6.12.* (semver)
Unaffected: 6.16.4 , ≤ 6.16.* (semver)
Unaffected: 6.17 , ≤ * (original_commit_for_fix)
guessed Create a notification for this product.
Siemens SIMATIC CN 4100 Affected: 0 , < V5.0 (custom)
guessed Create a notification for this product.
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          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet, hsr: reject HSR frame if skb can\u0027t hold tag\n\nReceiving HSR frame with insufficient space to hold HSR tag in the skb\ncan result in a crash (kernel BUG):\n\n[   45.390915] skbuff: skb_under_panic: text:ffffffff86f32cac len:26 put:14 head:ffff888042418000 data:ffff888042417ff4 tail:0xe end:0x180 dev:bridge_slave_1\n[   45.392559] ------------[ cut here ]------------\n[   45.392912] kernel BUG at net/core/skbuff.c:211!\n[   45.393276] Oops: invalid opcode: 0000 [#1] SMP DEBUG_PAGEALLOC KASAN NOPTI\n[   45.393809] CPU: 1 UID: 0 PID: 2496 Comm: reproducer Not tainted 6.15.0 #12 PREEMPT(undef)\n[   45.394433] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014\n[   45.395273] RIP: 0010:skb_panic+0x15b/0x1d0\n\n\u003csnip registers, remove unreliable trace\u003e\n\n[   45.402911] Call Trace:\n[   45.403105]  \u003cIRQ\u003e\n[   45.404470]  skb_push+0xcd/0xf0\n[   45.404726]  br_dev_queue_push_xmit+0x7c/0x6c0\n[   45.406513]  br_forward_finish+0x128/0x260\n[   45.408483]  __br_forward+0x42d/0x590\n[   45.409464]  maybe_deliver+0x2eb/0x420\n[   45.409763]  br_flood+0x174/0x4a0\n[   45.410030]  br_handle_frame_finish+0xc7c/0x1bc0\n[   45.411618]  br_handle_frame+0xac3/0x1230\n[   45.413674]  __netif_receive_skb_core.constprop.0+0x808/0x3df0\n[   45.422966]  __netif_receive_skb_one_core+0xb4/0x1f0\n[   45.424478]  __netif_receive_skb+0x22/0x170\n[   45.424806]  process_backlog+0x242/0x6d0\n[   45.425116]  __napi_poll+0xbb/0x630\n[   45.425394]  net_rx_action+0x4d1/0xcc0\n[   45.427613]  handle_softirqs+0x1a4/0x580\n[   45.427926]  do_softirq+0x74/0x90\n[   45.428196]  \u003c/IRQ\u003e\n\nThis issue was found by syzkaller.\n\nThe panic happens in br_dev_queue_push_xmit() once it receives a\ncorrupted skb with ETH header already pushed in linear data. When it\nattempts the skb_push() call, there\u0027s not enough headroom and\nskb_push() panics.\n\nThe corrupted skb is put on the queue by HSR layer, which makes a\nsequence of unintended transformations when it receives a specific\ncorrupted HSR frame (with incomplete TAG).\n\nFix it by dropping and consuming frames that are not long enough to\ncontain both ethernet and hsr headers.\n\nAlternative fix would be to check for enough headroom before skb_push()\nin br_dev_queue_push_xmit().\n\nIn the reproducer, this is injected via AF_PACKET, but I don\u0027t easily\nsee why it couldn\u0027t be sent over the wire from adjacent network.\n\nFurther Details:\n\nIn the reproducer, the following network interface chain is set up:\n\n\u250c\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2510   \u250c\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2510\n\u2502 veth0_to_hsr   \u251c\u2500\u2500\u2500\u2524  hsr_slave0    \u253c\u2500\u2500\u2500\u2510\n\u2514\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2518   \u2514\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2518   \u2502\n                                          \u2502 \u250c\u2500\u2500\u2500\u2500\u2500\u2500\u2510\n                                          \u251c\u2500\u2524 hsr0 \u251c\u2500\u2500\u2500\u2510\n                                          \u2502 \u2514\u2500\u2500\u2500\u2500\u2500\u2500\u2518   \u2502\n\u250c\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2510   \u250c\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2510   \u2502            \u2502\u250c\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2510\n\u2502 veth1_to_hsr   \u253c\u2500\u2500\u2500\u2524  hsr_slave1    \u251c\u2500\u2500\u2500\u2518            \u2514\u2524        \u2502\n\u2514\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2518   \u2514\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2518                \u250c\u253c bridge \u2502\n                                                       \u2502\u2502        \u2502\n                                                       \u2502\u2514\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2518\n                                                       \u2502\n                                        \u250c\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2510      \u2502\n                                        \u2502  ...  \u251c\u2500\u2500\u2500\u2500\u2500\u2500\u2518\n                                        \u2514\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2518\n\nTo trigger the events leading up to crash, reproducer sends a corrupted\nHSR fr\n---truncated---"
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              "value": "AV:N - The bug is triggered purely by a received HSR/PRP-tagged frame processed by the HSR rx_handler in net/hsr/, with no local access required. HSR slaves are commonly veth/tap/bridge/tunnel-backed in virtualized and industrial-gateway deployments, where an undersized inner Ethernet frame delivered through a routed L2-over-IP tunnel (VXLAN/GRE) reaches the handler from an arbitrary remote host.\nAC:L - The attacker only needs to send a single HSR/PRP frame shorter than ETH_HLEN + HSR_HLEN (20 bytes); the missing length check is hit deterministically on every such frame with no timing, race, or memory-layout precondition.\nPR:N - There is no authentication, capability check, or credential validation anywhere on the path from netif_receive_skb() through hsr_handle_frame() to hsr_forward_skb(); any unauthenticated sender of a frame on the HSR-enslaved link is sufficient.\nUI:N - Frame processing happens automatically in the NAPI/softirq receive path as soon as the frame arrives; no victim action is required.\nS:U - The corruption and its effects stay within the kernel network stack of the same host, with no crossing of a VM, IOMMU, or sandbox security authority.\nC:H - The corrupted mac_len/network_header cause out-of-bounds reads past skb-\u003etail in hsr_get_skb_sequence_nr() and create_stripped_skb_hsr(), and when headroom suffices br_dev_queue_push_xmit()\u0027s skb_push(ETH_HLEN) turns 14 bytes of uninitialized kernel heap into the Ethernet header of a frame that is then transmitted, disclosing kernel memory to the network.\nI:H - Attacker-controlled skb geometry corruption (network_header, mac_len, and len inconsistent with the linear buffer) propagates into the bridge/forwarding path where skb_push moves skb-\u003edata outside the intended data region, corrupting packet contents and providing the memory-corruption primitive that is only accidentally caught by the skb_under_panic BUG().\nA:H - The documented syzbot outcome is skb_under_panic() hitting BUG() at net/core/skbuff.c:211 from softirq/IRQ context, which is a fatal kernel panic, and it can be re-triggered at will with a single crafted frame."
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    "assignerShortName": "Linux",
    "cveId": "CVE-2025-39703",
    "datePublished": "2025-09-05T17:21:09.768Z",
    "dateReserved": "2025-04-16T07:20:57.115Z",
    "dateUpdated": "2026-08-05T12:04:42.024Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2025-39703",
      "date": "2026-09-16",
      "epss": "0.00364",
      "percentile": "0.30002"
    },
    "microsoft_vex": {
      "current_release_date": "2026-02-24T14:46:14.000Z",
      "cve": "CVE-2025-39703",
      "id": "msrc_CVE-2025-39703",
      "initial_release_date": "2025-09-02T00:00:00.000Z",
      "product_status:fixed": "2",
      "product_status:known_affected": "3",
      "source": "Microsoft CSAF VEX",
      "status": "final",
      "title": "net, hsr: reject HSR frame if skb can\u0027t hold tag",
      "url": "https://msrc.microsoft.com/csaf/vex/2025/msrc_cve-2025-39703.json",
      "version": "3"
    },
    "nvd": "{\"cve\":{\"id\":\"CVE-2025-39703\",\"sourceIdentifier\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"published\":\"2025-09-05T18:15:47.417\",\"lastModified\":\"2026-07-30T06:23:41.780\",\"vulnStatus\":\"Modified\",\"cveTags\":[],\"descriptions\":[{\"lang\":\"en\",\"value\":\"In the Linux kernel, the following vulnerability has been resolved:\\n\\nnet, hsr: reject HSR frame if skb can\u0027t hold tag\\n\\nReceiving HSR frame with insufficient space to hold HSR tag in the skb\\ncan result in a crash (kernel BUG):\\n\\n[   45.390915] skbuff: skb_under_panic: text:ffffffff86f32cac len:26 put:14 head:ffff888042418000 data:ffff888042417ff4 tail:0xe end:0x180 dev:bridge_slave_1\\n[   45.392559] ------------[ cut here ]------------\\n[   45.392912] kernel BUG at net/core/skbuff.c:211!\\n[   45.393276] Oops: invalid opcode: 0000 [#1] SMP DEBUG_PAGEALLOC KASAN NOPTI\\n[   45.393809] CPU: 1 UID: 0 PID: 2496 Comm: reproducer Not tainted 6.15.0 #12 PREEMPT(undef)\\n[   45.394433] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014\\n[   45.395273] RIP: 0010:skb_panic+0x15b/0x1d0\\n\\n\u003csnip registers, remove unreliable trace\u003e\\n\\n[   45.402911] Call Trace:\\n[   45.403105]  \u003cIRQ\u003e\\n[   45.404470]  skb_push+0xcd/0xf0\\n[   45.404726]  br_dev_queue_push_xmit+0x7c/0x6c0\\n[   45.406513]  br_forward_finish+0x128/0x260\\n[   45.408483]  __br_forward+0x42d/0x590\\n[   45.409464]  maybe_deliver+0x2eb/0x420\\n[   45.409763]  br_flood+0x174/0x4a0\\n[   45.410030]  br_handle_frame_finish+0xc7c/0x1bc0\\n[   45.411618]  br_handle_frame+0xac3/0x1230\\n[   45.413674]  __netif_receive_skb_core.constprop.0+0x808/0x3df0\\n[   45.422966]  __netif_receive_skb_one_core+0xb4/0x1f0\\n[   45.424478]  __netif_receive_skb+0x22/0x170\\n[   45.424806]  process_backlog+0x242/0x6d0\\n[   45.425116]  __napi_poll+0xbb/0x630\\n[   45.425394]  net_rx_action+0x4d1/0xcc0\\n[   45.427613]  handle_softirqs+0x1a4/0x580\\n[   45.427926]  do_softirq+0x74/0x90\\n[   45.428196]  \u003c/IRQ\u003e\\n\\nThis issue was found by syzkaller.\\n\\nThe panic happens in br_dev_queue_push_xmit() once it receives a\\ncorrupted skb with ETH header already pushed in linear data. When it\\nattempts the skb_push() call, there\u0027s not enough headroom and\\nskb_push() panics.\\n\\nThe corrupted skb is put on the queue by HSR layer, which makes a\\nsequence of unintended transformations when it receives a specific\\ncorrupted HSR frame (with incomplete TAG).\\n\\nFix it by dropping and consuming frames that are not long enough to\\ncontain both ethernet and hsr headers.\\n\\nAlternative fix would be to check for enough headroom before skb_push()\\nin br_dev_queue_push_xmit().\\n\\nIn the reproducer, this is injected via AF_PACKET, but I don\u0027t easily\\nsee why it couldn\u0027t be sent over the wire from adjacent network.\\n\\nFurther Details:\\n\\nIn the reproducer, the following network interface chain is set up:\\n\\n\u250c\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2510   \u250c\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2510\\n\u2502 veth0_to_hsr   \u251c\u2500\u2500\u2500\u2524  hsr_slave0    \u253c\u2500\u2500\u2500\u2510\\n\u2514\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2518   \u2514\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2518   \u2502\\n                                          \u2502 \u250c\u2500\u2500\u2500\u2500\u2500\u2500\u2510\\n                                          \u251c\u2500\u2524 hsr0 \u251c\u2500\u2500\u2500\u2510\\n                                          \u2502 \u2514\u2500\u2500\u2500\u2500\u2500\u2500\u2518   \u2502\\n\u250c\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2510   \u250c\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2510   \u2502            \u2502\u250c\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2510\\n\u2502 veth1_to_hsr   \u253c\u2500\u2500\u2500\u2524  hsr_slave1    \u251c\u2500\u2500\u2500\u2518            \u2514\u2524        \u2502\\n\u2514\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2518   \u2514\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2518                \u250c\u253c bridge \u2502\\n                                                       \u2502\u2502        \u2502\\n                                                       \u2502\u2514\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2518\\n                                                       \u2502\\n                                        \u250c\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2510      \u2502\\n                                        \u2502  ...  \u251c\u2500\u2500\u2500\u2500\u2500\u2500\u2518\\n                                        \u2514\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2518\\n\\nTo trigger the events leading up to crash, reproducer sends a corrupted\\nHSR fr\\n---truncated---\"}],\"affected\":[{\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"affectedData\":[{\"vendor\":\"Linux\",\"product\":\"Linux\",\"defaultStatus\":\"unaffected\",\"programFiles\":[\"net/hsr/hsr_slave.c\"],\"repo\":\"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\"versions\":[{\"version\":\"f6442ee08fe66c8e45c4f246531a2aaf4f17a7a7\",\"lessThan\":\"8d9bc4a375a1ba05f7dfa0407de8e510ab9bd14d\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"48b491a5cc74333c4a6a82fe21cea42c055a3b0b\",\"lessThan\":\"3ae272ab523dd6bdc26e879027ed79feac9dd1b3\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"48b491a5cc74333c4a6a82fe21cea42c055a3b0b\",\"lessThan\":\"b640188b8a6690e685939053c7efdbc7818b5f4e\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"48b491a5cc74333c4a6a82fe21cea42c055a3b0b\",\"lessThan\":\"b117c41b00902c1a7e24347c405cb82504aeae0b\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"48b491a5cc74333c4a6a82fe21cea42c055a3b0b\",\"lessThan\":\"acd69b597bd3f76d3b3d322b84082226c00eeaa4\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"48b491a5cc74333c4a6a82fe21cea42c055a3b0b\",\"lessThan\":\"61009439e4bd8d74e705ee15940760321be91d8a\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"48b491a5cc74333c4a6a82fe21cea42c055a3b0b\",\"lessThan\":\"7af76e9d18a9fd6f8611b3313c86c190f9b6a5a7\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"4ffd1d4a6b306ff69cbe412d2c54d2dd349ff436\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"5.10.42\",\"lessThan\":\"5.10.241\",\"versionType\":\"semver\",\"status\":\"affected\"},{\"version\":\"5.12.9\",\"lessThan\":\"5.13\",\"versionType\":\"semver\",\"status\":\"affected\"}]},{\"vendor\":\"Linux\",\"product\":\"Linux\",\"defaultStatus\":\"affected\",\"programFiles\":[\"net/hsr/hsr_slave.c\"],\"repo\":\"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\"versions\":[{\"version\":\"5.13\",\"status\":\"affected\"},{\"version\":\"0\",\"lessThan\":\"5.13\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"5.10.241\",\"lessThanOrEqual\":\"5.10.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"5.15.190\",\"lessThanOrEqual\":\"5.15.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.1.149\",\"lessThanOrEqual\":\"6.1.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.6.103\",\"lessThanOrEqual\":\"6.6.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.12.44\",\"lessThanOrEqual\":\"6.12.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.16.4\",\"lessThanOrEqual\":\"6.16.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.17\",\"lessThanOrEqual\":\"*\",\"versionType\":\"original_commit_for_fix\",\"status\":\"unaffected\"}]}]},{\"source\":\"0b142b55-0307-4c5a-b3c9-f314f3fb7c5e\",\"affectedData\":[{\"vendor\":\"Siemens\",\"product\":\"SIMATIC CN 4100\",\"defaultStatus\":\"unknown\",\"versions\":[{\"version\":\"0\",\"lessThan\":\"V5.0\",\"versionType\":\"custom\",\"status\":\"affected\"}]}]}],\"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},{\"source\":\"nvd@nist.gov\",\"type\":\"Primary\",\"cvssData\":{\"version\":\"3.1\",\"vectorString\":\"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H\",\"baseScore\":5.5,\"baseSeverity\":\"MEDIUM\",\"attackVector\":\"LOCAL\",\"attackComplexity\":\"LOW\",\"privilegesRequired\":\"LOW\",\"userInteraction\":\"NONE\",\"scope\":\"UNCHANGED\",\"confidentialityImpact\":\"NONE\",\"integrityImpact\":\"NONE\",\"availabilityImpact\":\"HIGH\"},\"exploitabilityScore\":1.8,\"impactScore\":3.6}]},\"weaknesses\":[{\"source\":\"nvd@nist.gov\",\"type\":\"Primary\",\"description\":[{\"lang\":\"en\",\"value\":\"CWE-476\"}]}],\"configurations\":[{\"nodes\":[{\"operator\":\"OR\",\"negate\":false,\"cpeMatch\":[{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\",\"versionStartIncluding\":\"5.10.42\",\"versionEndExcluding\":\"5.10.241\",\"matchCriteriaId\":\"9C58D49B-1D68-47E6-B1DF-DAAA14EF9624\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\",\"versionStartIncluding\":\"5.12.9\",\"versionEndExcluding\":\"5.13\",\"matchCriteriaId\":\"44F871E1-E26F-4DFD-8BEC-BD33F0B9304B\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\",\"versionStartIncluding\":\"5.13.1\",\"versionEndExcluding\":\"5.15.190\",\"matchCriteriaId\":\"E4582D5F-A037-4D79-8407-4DBB2A87E1A2\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\",\"versionStartIncluding\":\"5.16\",\"versionEndExcluding\":\"6.1.149\",\"matchCriteriaId\":\"FDBE8280-8983-4D2D-943D-2E6D0104E2D8\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\",\"versionStartIncluding\":\"6.2\",\"versionEndExcluding\":\"6.6.103\",\"matchCriteriaId\":\"F2293654-7169-49B5-8D0D-EE51EF8B8E48\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\",\"versionStartIncluding\":\"6.7\",\"versionEndExcluding\":\"6.12.44\",\"matchCriteriaId\":\"12351F24-1133-4775-960C-F2B47E81298B\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\",\"versionStartIncluding\":\"6.13\",\"versionEndExcluding\":\"6.16.4\",\"matchCriteriaId\":\"AFC28995-B8C3-4B68-8CB6-78E792B6629D\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:5.13:-:*:*:*:*:*:*\",\"matchCriteriaId\":\"8F0E7012-0BA3-4E6A-ADE9-57973CBDEE28\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:5.13:rc4:*:*:*:*:*:*\",\"matchCriteriaId\":\"1ECD33F5-85BE-430B-8F86-8D7BD560311D\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:5.13:rc5:*:*:*:*:*:*\",\"matchCriteriaId\":\"CF351855-2437-4CF5-AD7C-BDFA51F27683\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:5.13:rc6:*:*:*:*:*:*\",\"matchCriteriaId\":\"25A855BA-2118-44F2-90EF-EBBB12AF51EF\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:5.13:rc7:*:*:*:*:*:*\",\"matchCriteriaId\":\"F63101C7-E7A3-4C74-9CD5-B5FC5F53F5C8\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:6.17:rc1:*:*:*:*:*:*\",\"matchCriteriaId\":\"327D22EF-390B-454C-BD31-2ED23C998A1C\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:6.17:rc2:*:*:*:*:*:*\",\"matchCriteriaId\":\"C730CD9A-D969-4A8E-9522-162AAF7C0EE9\"}]}]},{\"nodes\":[{\"operator\":\"OR\",\"negate\":false,\"cpeMatch\":[{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:*\",\"matchCriteriaId\":\"FA6FEEC2-9F11-4643-8827-749718254FED\"}]}]}],\"references\":[{\"url\":\"https://git.kernel.org/stable/c/3ae272ab523dd6bdc26e879027ed79feac9dd1b3\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"tags\":[\"Patch\"]},{\"url\":\"https://git.kernel.org/stable/c/61009439e4bd8d74e705ee15940760321be91d8a\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"tags\":[\"Patch\"]},{\"url\":\"https://git.kernel.org/stable/c/7af76e9d18a9fd6f8611b3313c86c190f9b6a5a7\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"tags\":[\"Patch\"]},{\"url\":\"https://git.kernel.org/stable/c/8d9bc4a375a1ba05f7dfa0407de8e510ab9bd14d\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"tags\":[\"Patch\"]},{\"url\":\"https://git.kernel.org/stable/c/acd69b597bd3f76d3b3d322b84082226c00eeaa4\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"tags\":[\"Patch\"]},{\"url\":\"https://git.kernel.org/stable/c/b117c41b00902c1a7e24347c405cb82504aeae0b\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"tags\":[\"Patch\"]},{\"url\":\"https://git.kernel.org/stable/c/b640188b8a6690e685939053c7efdbc7818b5f4e\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"tags\":[\"Patch\"]},{\"url\":\"https://lists.debian.org/debian-lts-announce/2025/10/msg00007.html\",\"source\":\"af854a3a-2127-422b-91ae-364da2661108\",\"tags\":[\"Mailing List\",\"Third Party Advisory\"]},{\"url\":\"https://lists.debian.org/debian-lts-announce/2025/10/msg00008.html\",\"source\":\"af854a3a-2127-422b-91ae-364da2661108\",\"tags\":[\"Mailing List\",\"Third Party Advisory\"]},{\"url\":\"https://cert-portal.siemens.com/productcert/html/ssa-032379.html\",\"source\":\"0b142b55-0307-4c5a-b3c9-f314f3fb7c5e\"}]}}",
    "redhat_vex": {
      "aggregate_severity": "Moderate",
      "current_release_date": "2026-07-30T08:58:33+00:00",
      "cve": "CVE-2025-39703",
      "id": "CVE-2025-39703",
      "initial_release_date": "2025-09-05T00:00:00+00:00",
      "product_status:known_affected": "184",
      "product_status:known_not_affected": "90",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: net, hsr: reject HSR frame if skb can\u0027t hold tag",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2025/cve-2025-39703.json",
      "version": "3"
    },
    "suse_vex": {
      "aggregate_severity": "moderate",
      "current_release_date": "2026-08-31T00:18:57Z",
      "cve": "CVE-2025-39703",
      "id": "CVE-2025-39703",
      "initial_release_date": "2026-05-24T00:56:35Z",
      "product_status:first_fixed": "2",
      "product_status:known_affected": "349",
      "product_status:known_not_affected": "262",
      "product_status:recommended": "678",
      "source": "SUSE CSAF VEX",
      "status": "interim",
      "title": "SUSE CVE CVE-2025-39703",
      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2025-39703.json",
      "version": "13"
    }
  }
}



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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.


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.