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

Vulnerability from cvelistv5 – Published: 2026-10-23 12:23 – Updated: 2026-10-30 12:41
VLAI
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 6653 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: 680aea08e78c003292415518ad270bc20f9c80b1 , < 8b35e7767fdee63e57948a1ec89d9238a651f8c6 (git)
Affected: 680aea08e78c003292415518ad270bc20f9c80b1 , < 096ad0cb77f8da1928d04a0d170535e14ca6311b (git)
Affected: 680aea08e78c003292415518ad270bc20f9c80b1 , < 088ba80eef85fa7a5ad8f9e7c82b403c99242b56 (git)
Affected: 680aea08e78c003292415518ad270bc20f9c80b1 , < 78a1cf5c54b2f795c81fedb530755a8d01cc84f0 (git)
Affected: 680aea08e78c003292415518ad270bc20f9c80b1 , < 7dfa7ca97f3ac46353edd4cc44f7733758e4535b (git)
Affected: 680aea08e78c003292415518ad270bc20f9c80b1 , < 221ef5e1e44a044790f0f54e6aa237883f475a4d (git)
Affected: 680aea08e78c003292415518ad270bc20f9c80b1 , < e02a5b6588161673ef75a4bc5cdfb62bd493374d (git)
guessed Create a notification for this product.
Linux Linux Affected: 5.12
Unaffected: 0 , < 5.12 (semver)
Unaffected: 5.15.224 , ≤ 5.15.* (semver)
Unaffected: 6.1.191 , ≤ 6.1.* (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)
guessed Create a notification for this product.
Show details on NVD website
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}



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