Unscored severity · published Oct 23, 2026
CVE-2026-99071
ipv4: do not warn on route notification size race
New
–
CVSS
0.2%
EPSS
No
On KEV
Description
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.
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 10% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
LI
Linux · Linux
680aea08e78c003292415518ad270bc20f9c80b1 before 088ba80eef85fa7a5ad8f9e7c82b403c99242b56; 680aea08e78c003292415518ad270bc20f9c80b1 before 78a1cf5c54b2f795c81fedb530755a8d01cc84f0; 680aea08e78c003292415518ad270bc20f9c80b1 before 7dfa7ca97f3ac46353edd4cc44f7733758e4535b; 680aea08e78c003292415518ad270bc20f9c80b1 before 221ef5e1e44a044790f0f54e6aa237883f475a4d; 680aea08e78c003292415518ad270bc20f9c80b1 before e02a5b6588161673ef75a4bc5cdfb62bd493374d; 5.12 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-99071
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-99071
git.kernel.org
https://git.kernel.org/stable/c/088ba80eef85fa7a5ad8f9e7c82b403c99242b56
git.kernel.org
https://git.kernel.org/stable/c/221ef5e1e44a044790f0f54e6aa237883f475a4d
git.kernel.org
https://git.kernel.org/stable/c/78a1cf5c54b2f795c81fedb530755a8d01cc84f0
git.kernel.org
https://git.kernel.org/stable/c/7dfa7ca97f3ac46353edd4cc44f7733758e4535b
git.kernel.org
https://git.kernel.org/stable/c/e02a5b6588161673ef75a4bc5cdfb62bd493374d
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