Description
In the Linux kernel, the following vulnerability has been resolved: net/ip6_tunnel: Prevent perpetual tunnel growth Similarly to ipv4 tunnel, ipv6 version updates dev->needed_headroom, too. While ipv4 tunnel headroom adjustment growth was limited in commit 5ae1e9922bbd ("net: ip_tunnel: prevent perpetual headroom growth"), ipv6 tunnel yet increases the headroom without any ceiling. Reflect ipv4 tunnel headroom adjustment limit on ipv6 version. Credits to Francesco Ruggeri, who was originally debugging this issue and wrote local Arista-specific patch and a reproducer.
References8
- git.kernel.org/stable/c/10fe967efe73c610e526ff7460581610633dee9c
- git.kernel.org/stable/c/11f6066af3bfb8149aa16c42c0b0c5ea5b199a94
- git.kernel.org/stable/c/21f4d45eba0b2dcae5dbc9e5e0ad08735c993f16
- git.kernel.org/stable/c/402b6985e872b4cf394bbbf33b503947a326a6cb
- git.kernel.org/stable/c/48294a67863c9cfa367abb66bbf0ef6548ae124f
- git.kernel.org/stable/c/566f8d5c8a443f2dd69c5460fdec43ed1c870c65
- git.kernel.org/stable/c/b6eb25d870f1a8ae571fd3da2244b71df547824b
- git.kernel.org/stable/c/eeb4345488672584db4f8c20a1ae13a212ce31c4
Metrics
- CVSS 3.1
-
7.8
HIGH
Score source: CNA
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H - EPSS — exploit probability
- 0% percentile: 5 · as of 10 November 2026
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