Heap-based Buffer Overflow The advisory has been revoked - it doesn't affect any version of package kernel-headers (opens in a new tab)
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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Test your applications- Snyk IDSNYK-RHEL10-KERNELHEADERS-13966557
- published14 Nov 2025
- disclosed12 Nov 2025
Introduced: 12 Nov 2025
CVE-2025-40173 (opens in a new tab)Amendment
The Red Hat security team deemed this advisory irrelevant for RHEL:10.
NVD Description
Note: Versions mentioned in the description apply only to the upstream kernel-headers package and not the kernel-headers package as distributed by RHEL.
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://bugzilla.redhat.com/show_bug.cgi?id=2414492
- https://access.redhat.com/security/cve/CVE-2025-40173
- https://git.kernel.org/stable/c/10fe967efe73c610e526ff7460581610633dee9c
- https://git.kernel.org/stable/c/11f6066af3bfb8149aa16c42c0b0c5ea5b199a94
- https://git.kernel.org/stable/c/21f4d45eba0b2dcae5dbc9e5e0ad08735c993f16
- https://git.kernel.org/stable/c/402b6985e872b4cf394bbbf33b503947a326a6cb
- https://git.kernel.org/stable/c/48294a67863c9cfa367abb66bbf0ef6548ae124f
- https://git.kernel.org/stable/c/566f8d5c8a443f2dd69c5460fdec43ed1c870c65
- https://git.kernel.org/stable/c/b6eb25d870f1a8ae571fd3da2244b71df547824b
- https://git.kernel.org/stable/c/eeb4345488672584db4f8c20a1ae13a212ce31c4