Vulnerability-Lookup

GHSA-3VR4-GX8Q-4FGG

Vulnerability from github – Published: 2025-11-12 12:30 – Updated: 2026-07-30 06:32

Details

In the Linux kernel, the following vulnerability has been resolved:

net: use dst_dev_rcu() in sk_setup_caps()

Use RCU to protect accesses to dst->dev from sk_setup_caps() and sk_dst_gso_max_size().

Also use dst_dev_rcu() in ip6_dst_mtu_maybe_forward(), and ip_dst_mtu_maybe_forward().

ip4_dst_hoplimit() can use dst_dev_net_rcu().

Severity

7.8 (High)


                  
                    CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Show details on source website

JSON

To clipboard

{
  "affected": [],
  "aliases": [
    "CVE-2025-40170"
  ],
  "database_specific": {
    "cwe_ids": [],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2025-11-12T11:15:47Z",
    "severity": "HIGH"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet: use dst_dev_rcu() in sk_setup_caps()\n\nUse RCU to protect accesses to dst-\u003edev from sk_setup_caps()\nand sk_dst_gso_max_size().\n\nAlso use dst_dev_rcu() in ip6_dst_mtu_maybe_forward(),\nand ip_dst_mtu_maybe_forward().\n\nip4_dst_hoplimit() can use dst_dev_net_rcu().",
  "id": "GHSA-3vr4-gx8q-4fgg",
  "modified": "2026-07-30T06:32:17Z",
  "published": "2025-11-12T12:30:28Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2025-40170"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/5d1be493d1110c9e720b4c51a6e587bb2fb4ac12"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/99a2ace61b211b0be861b07fbaa062fca4b58879"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/a805729c0091073d8f0415cfa96c7acd1bc17a48"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ]
}

CVE-2025-40170 (GCVE-0-2025-40170)

Vulnerability from cvelistv5 – Published: 2025-11-12 10:46 – Updated: 2026-08-05 12:08

Title

net: use dst_dev_rcu() in sk_setup_caps()

Summary

In the Linux kernel, the following vulnerability has been resolved: net: use dst_dev_rcu() in sk_setup_caps() Use RCU to protect accesses to dst->dev from sk_setup_caps() and sk_dst_gso_max_size(). Also use dst_dev_rcu() in ip6_dst_mtu_maybe_forward(), and ip_dst_mtu_maybe_forward(). ip4_dst_hoplimit() can use dst_dev_net_rcu().

Severity

7.8 (High)


                        
                          CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

SSVC

Exploitation: none Automatable: yes Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-06-16 19:33 UTC

Assigner

Linux mitre root

References

3 references

URL	Tags
https://git.kernel.org/stable/c/5d1be493d1110c9e7…
https://git.kernel.org/stable/c/a805729c0091073d8…
https://git.kernel.org/stable/c/99a2ace61b211b0be…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: 4a6ce2b6f2ecabbddcfe47e7cf61dd0f00b10e36 , < 5d1be493d1110c9e720b4c51a6e587bb2fb4ac12 (git) Affected: 4a6ce2b6f2ecabbddcfe47e7cf61dd0f00b10e36 , < a805729c0091073d8f0415cfa96c7acd1bc17a48 (git) Affected: 4a6ce2b6f2ecabbddcfe47e7cf61dd0f00b10e36 , < 99a2ace61b211b0be861b07fbaa062fca4b58879 (git)
Linux	Linux	Affected: 4.13 Unaffected: 0 , < 4.13 (semver) Unaffected: 6.12.64 , ≤ 6.12.* (semver) Unaffected: 6.17.3 , ≤ 6.17.* (semver) Unaffected: 6.18 , ≤ * (original_commit_for_fix)

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2025-40170",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "yes"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-06-16T19:33:10.426175Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-06-16T19:33:20.303Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "include/net/ip.h",
            "include/net/ip6_route.h",
            "include/net/route.h",
            "net/core/sock.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "5d1be493d1110c9e720b4c51a6e587bb2fb4ac12",
              "status": "affected",
              "version": "4a6ce2b6f2ecabbddcfe47e7cf61dd0f00b10e36",
              "versionType": "git"
            },
            {
              "lessThan": "a805729c0091073d8f0415cfa96c7acd1bc17a48",
              "status": "affected",
              "version": "4a6ce2b6f2ecabbddcfe47e7cf61dd0f00b10e36",
              "versionType": "git"
            },
            {
              "lessThan": "99a2ace61b211b0be861b07fbaa062fca4b58879",
              "status": "affected",
              "version": "4a6ce2b6f2ecabbddcfe47e7cf61dd0f00b10e36",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "include/net/ip.h",
            "include/net/ip6_route.h",
            "include/net/route.h",
            "net/core/sock.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "4.13"
            },
            {
              "lessThan": "4.13",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.64",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.17.*",
              "status": "unaffected",
              "version": "6.17.3",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "6.18",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.12.64",
                  "versionStartIncluding": "4.13",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.17.3",
                  "versionStartIncluding": "4.13",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.18",
                  "versionStartIncluding": "4.13",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet: use dst_dev_rcu() in sk_setup_caps()\n\nUse RCU to protect accesses to dst-\u003edev from sk_setup_caps()\nand sk_dst_gso_max_size().\n\nAlso use dst_dev_rcu() in ip6_dst_mtu_maybe_forward(),\nand ip_dst_mtu_maybe_forward().\n\nip4_dst_hoplimit() can use dst_dev_net_rcu()."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "baseScore": 7.8,
            "baseSeverity": "HIGH",
            "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
            "version": "3.1"
          },
          "scenarios": [
            {
              "lang": "en",
              "value": "AV:L - The unprotected `sk_setup_caps()` reader is reached from process-context syscalls (connect/sendmsg/SCTP output), and the racing `dst_dev_put()`/netdev-unregister side requires local netns and link/route manipulation; the remote-triggered call site (`tcp_v4_syn_recv_sock`) runs BH-disabled and is implicitly RCU-protected.\nAC:L - The attacker controls both sides of the race \u2014 one thread loops connect()/sendmsg() on sockets holding the dst while another deletes the veth/route in its own netns \u2014 and can retry indefinitely until the window is hit.\nPR:L - An unprivileged local account suffices; CAP_NET_ADMIN needed for link/route teardown is obtainable without real root via user namespaces (`unshare -Urn`), and the socket side needs no privilege at all.\nUI:N - Exploitation is entirely driven by the attacker\u0027s own threads issuing socket syscalls and netlink link/route operations; no victim action is required.\nS:U - The use-after-free is on a kernel `struct net_device` and its effects stay within the kernel\u0027s own security authority, with no crossing of a VM, IOMMU, or sandbox boundary.\nC:H - This is a use-after-free read of a freed, heap-sprayable `net_device`; its contents are loaded into `sk_route_caps`, `sk_gso_max_size` and `sk_gso_max_segs`, which observably alter TCP segmentation and thus leak freed-memory contents, and per UAF guidance this is High.\nI:H - Values read from freed memory are written into persistent socket state and then drive packet construction \u2014 bogus SG/HW_CSUM/GSO feature bits and an underflowed multi-gigabyte `sk_gso_max_size` corrupt the TX path, and a UAF on a sprayable object is treatable as an arbitrary-write primitive.\nA:H - Dereferencing a freed `net_device` can oops outright, and the resulting garbage GSO sizes/segment counts produce oversized skb allocations and inconsistent offload state that crash the transmit path and drivers."
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-05T12:08:15.716Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/5d1be493d1110c9e720b4c51a6e587bb2fb4ac12"
        },
        {
          "url": "https://git.kernel.org/stable/c/a805729c0091073d8f0415cfa96c7acd1bc17a48"
        },
        {
          "url": "https://git.kernel.org/stable/c/99a2ace61b211b0be861b07fbaa062fca4b58879"
        }
      ],
      "title": "net: use dst_dev_rcu() in sk_setup_caps()",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2025-40170",
    "datePublished": "2025-11-12T10:46:52.014Z",
    "dateReserved": "2025-04-16T07:20:57.176Z",
    "dateUpdated": "2026-08-05T12:08:15.716Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

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.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.

Action not permitted

GHSA-3VR4-GX8Q-4FGG

CVE-2025-40170 (GCVE-0-2025-40170)

Tags

Sightings

Nomenclature