CVEvulnerability
CVE-2025-40173
7.8 HIGH
Official page ↗
- Status
- Deferred
- Published
- 2025-11-12
- Last modified
- 2026-10-19
- Assigner
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
- CVSS 3.1 (416baaa9-dc9f-4396-8d5f-8c081fb06d67)
- 7.8 HIGH — CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
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.
References
- https://git.kernel.org/stable/c/10fe967efe73c610e526ff7460581610633dee9c git.kernel.org
- https://git.kernel.org/stable/c/11f6066af3bfb8149aa16c42c0b0c5ea5b199a94 git.kernel.org
- https://git.kernel.org/stable/c/21f4d45eba0b2dcae5dbc9e5e0ad08735c993f16 git.kernel.org
- https://git.kernel.org/stable/c/402b6985e872b4cf394bbbf33b503947a326a6cb git.kernel.org
- https://git.kernel.org/stable/c/48294a67863c9cfa367abb66bbf0ef6548ae124f git.kernel.org
- https://git.kernel.org/stable/c/566f8d5c8a443f2dd69c5460fdec43ed1c870c65 git.kernel.org
- https://git.kernel.org/stable/c/b6eb25d870f1a8ae571fd3da2244b71df547824b git.kernel.org
- https://git.kernel.org/stable/c/eeb4345488672584db4f8c20a1ae13a212ce31c4 git.kernel.org