Description
In the Linux kernel, the following vulnerability has been resolved: vxlan: use neigh_ha_snapshot() in route_shortcircuit() The neighbour hardware address n->ha can be updated asynchronously by the neighbour subsystem, protected by n->ha_lock seqlock. Reading n->ha without holding the seqlock loop can lead to torn reads or reading a partially updated MAC address. Use neigh_ha_snapshot() in route_shortcircuit() to safely copy n->ha under read_seqbegin()/read_seqretry() lock protection before using it. Note that arp_reduce() and neigh_reduce() seem to have the same issue left for future patches.
References8
- git.kernel.org/stable/c/05f2987f73daa05333fd713d05546142f9f7c5f0
- git.kernel.org/stable/c/32a9590a8d30426e3db63e6b20893e47e02576c0
- git.kernel.org/stable/c/87210054bad82bbae6f483a742dc45722fb47a6b
- git.kernel.org/stable/c/8eca411347e1d38964f9ed2c8d3b6ab0e7e4473d
- git.kernel.org/stable/c/d08e8ac13f2e228cc7fc3c70b5ebe71557b624a0
- git.kernel.org/stable/c/d0993fc053f29e15cc7c9fe2029df3882a2ab5ab
- git.kernel.org/stable/c/ec341bb76d77b4c2948764375ee6bfeef4bb41c3
- git.kernel.org/stable/c/ff89415d34c3ab9f5312316423122e664ed3524f
Metrics
- CVSS 3.1
-
10.0
CRITICAL
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:L - EPSS — exploit probability
- 0% percentile: 40 · as of 11 November 2026
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