Vulnerability-Lookup

GHSA-66G6-R4V9-4XGM

Vulnerability from github – Published: 2026-10-23 15:31 – Updated: 2026-10-23 15:31

Details

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

ipv4: do not warn on route notification size race

Commit 680aea08e78c ("net: ipv4: Emit notification when fib hardware flags are changed") added asynchronous route notifications for hardware flag changes.

fib_alias_hw_flags_set() sizes the skb with fib_nlmsg_size() and later fills it with fib_dump_info() while holding only RCU. With nexthop compatibility mode enabled, a concurrent replacement can grow the group between these independent snapshots. fib_dump_info() can then legitimately return -EMSGSIZE, so the warning does not prove a sizing bug.

Remove the warning. The existing error path still frees the skb and reports the error to listeners.

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{
  "affected": [],
  "aliases": [
    "CVE-2026-99071"
  ],
  "database_specific": {
    "cwe_ids": [],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-10-23T13:17:31Z",
    "severity": null
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nipv4: do not warn on route notification size race\n\nCommit 680aea08e78c (\"net: ipv4: Emit notification when fib hardware\nflags are changed\") added asynchronous route notifications for hardware\nflag changes.\n\nfib_alias_hw_flags_set() sizes the skb with fib_nlmsg_size() and later\nfills it with fib_dump_info() while holding only RCU.  With nexthop\ncompatibility mode enabled, a concurrent replacement can grow the group\nbetween these independent snapshots.  fib_dump_info() can then\nlegitimately return -EMSGSIZE, so the warning does not prove a sizing bug.\n\nRemove the warning.  The existing error path still frees the skb and\nreports the error to listeners.",
  "id": "GHSA-66g6-r4v9-4xgm",
  "modified": "2026-10-23T15:31:37Z",
  "published": "2026-10-23T15:31:37Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-99071"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/088ba80eef85fa7a5ad8f9e7c82b403c99242b56"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/221ef5e1e44a044790f0f54e6aa237883f475a4d"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/78a1cf5c54b2f795c81fedb530755a8d01cc84f0"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/7dfa7ca97f3ac46353edd4cc44f7733758e4535b"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/e02a5b6588161673ef75a4bc5cdfb62bd493374d"
    }
  ],
  "schema_version": "1.4.0",
  "severity": []
}

CVE-2026-99071 (GCVE-0-2026-99071)

Vulnerability from cvelistv5 – Published: 2026-10-23 12:23 – Updated: 2026-10-23 12:23

Title

ipv4: do not warn on route notification size race

Summary

In the Linux kernel, the following vulnerability has been resolved: ipv4: do not warn on route notification size race Commit 680aea08e78c ("net: ipv4: Emit notification when fib hardware flags are changed") added asynchronous route notifications for hardware flag changes. fib_alias_hw_flags_set() sizes the skb with fib_nlmsg_size() and later fills it with fib_dump_info() while holding only RCU. With nexthop compatibility mode enabled, a concurrent replacement can grow the group between these independent snapshots. fib_dump_info() can then legitimately return -EMSGSIZE, so the warning does not prove a sizing bug. Remove the warning. The existing error path still frees the skb and reports the error to listeners.

Severity

No CVSS data available.

Assigner

Linux CNA under the mitre root

CNA scorecard D 53/100 over 7063 records in the last 180 days details

References

5 references

URL	Tags
https://git.kernel.org/stable/c/088ba80eef85fa7a5…
https://git.kernel.org/stable/c/78a1cf5c54b2f795c…
https://git.kernel.org/stable/c/7dfa7ca97f3ac4635…
https://git.kernel.org/stable/c/221ef5e1e44a04479…
https://git.kernel.org/stable/c/e02a5b6588161673e…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: 680aea08e78c003292415518ad270bc20f9c80b1 , < 088ba80eef85fa7a5ad8f9e7c82b403c99242b56 (git) Affected: 680aea08e78c003292415518ad270bc20f9c80b1 , < 78a1cf5c54b2f795c81fedb530755a8d01cc84f0 (git) Affected: 680aea08e78c003292415518ad270bc20f9c80b1 , < 7dfa7ca97f3ac46353edd4cc44f7733758e4535b (git) Affected: 680aea08e78c003292415518ad270bc20f9c80b1 , < 221ef5e1e44a044790f0f54e6aa237883f475a4d (git) Affected: 680aea08e78c003292415518ad270bc20f9c80b1 , < e02a5b6588161673ef75a4bc5cdfb62bd493374d (git)
Linux	Linux	Affected: 5.12 Unaffected: 0 , < 5.12 (semver) Unaffected: 6.6.160 , ≤ 6.6.* (semver) Unaffected: 6.12.113 , ≤ 6.12.* (semver) Unaffected: 6.18.57 , ≤ 6.18.* (semver) Unaffected: 7.2.11 , ≤ 7.2.* (semver) Unaffected: 7.3 , ≤ * (original_commit_for_fix)

Show details on NVD website

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          "programFiles": [
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              "versionType": "semver"
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              "lessThanOrEqual": "7.2.*",
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              "versionType": "semver"
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              "status": "unaffected",
              "version": "7.3",
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}

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.

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