Use-after-free in Linux kernel - CVE-2026-74705
Published: August 24, 2026
Vulnerability identifier: #VU144621
CSH Severity: Low
CVSS v4: 6.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-74705
CWE-ID: CWE-416
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a local attacker to cause a denial of service.
The vulnerability exists due to use-after-free in __skb_udp_tunnel_segment() in net/ipv4/udp_offload.c when processing tunnel segmentation for skb data after pulling the tunnel header into the skb head. A local attacker can trigger skb head reallocation and subsequent use of a stale UDP header pointer to cause a denial of service.
Affected software
Linux kernel
Debian Linux
linux (Debian package)
Debian Linux
linux (Debian package)
How to mitigate CVE-2026-74705
Install security update from vendor's repository.
Linux kernel - update to 7.0 rc3
linux (Debian package) - update to 6.12.105-1
linux (Debian package) - update to 6.12.105-1
External References
- https://git.kernel.org/stable/c/19d89b13a43640b2da2f277ee462d919d988cb6f
- https://git.kernel.org/stable/c/1ae134c012e10384cdac420b5cc6e0615cde0b55
- https://git.kernel.org/stable/c/5161e67c561c4f28a5d9335a6e859b02511de92b
- https://git.kernel.org/stable/c/588d4a6795d99d080f74ef0b5f391ea8c453ae5d
- https://git.kernel.org/stable/c/64d322c288577793eedd352b96ef75234ed380fe
- https://git.kernel.org/stable/c/6a733a38b983d8c2e222f13968209010cf44de87
- https://git.kernel.org/stable/c/b3df61bb745eb5201eac22679a2839d4ccbf3442
- https://git.kernel.org/stable/c/d0f86fb36eb260abd10007b62c9dcc1028e03e61