Description
In the Linux kernel, the following vulnerability has been resolved: udp: fix potential use-after-free in tunnel segmentation __skb_udp_tunnel_segment() gets the UDP header before ensuring the tunnel header is in the skb head. If the pull reallocates skb->head, the saved UDP header pointer is no longer valid. Get the UDP header after the pull to avoid a potential use-after-free.
References8
- git.kernel.org/stable/c/19d89b13a43640b2da2f277ee462d919d988cb6f
- git.kernel.org/stable/c/1ae134c012e10384cdac420b5cc6e0615cde0b55
- git.kernel.org/stable/c/5161e67c561c4f28a5d9335a6e859b02511de92b
- git.kernel.org/stable/c/588d4a6795d99d080f74ef0b5f391ea8c453ae5d
- git.kernel.org/stable/c/64d322c288577793eedd352b96ef75234ed380fe
- git.kernel.org/stable/c/6a733a38b983d8c2e222f13968209010cf44de87
- git.kernel.org/stable/c/b3df61bb745eb5201eac22679a2839d4ccbf3442
- git.kernel.org/stable/c/d0f86fb36eb260abd10007b62c9dcc1028e03e61
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:H - EPSS — exploit probability
- 0% percentile: 43 · as of 9 November 2026
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