CVE-2026-74705 PUBLISHED

udp: fix potential use-after-free in tunnel segmentation

Assigner: Linux
Reserved: 15.08.2026 Published: 22.08.2026 Updated: 22.08.2026

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head, the saved UDP header pointer is no longer valid.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.

Product Status

Vendor Linux
Product Linux
Versions Default: unaffected
  • affected from dbef491ebe7f3a4fb1b9111878b86a426fd540b7 to 6a733a38b983d8c2e222f13968209010cf44de87 (excl.)
  • affected from dbef491ebe7f3a4fb1b9111878b86a426fd540b7 to 19d89b13a43640b2da2f277ee462d919d988cb6f (excl.)
  • affected from dbef491ebe7f3a4fb1b9111878b86a426fd540b7 to b3df61bb745eb5201eac22679a2839d4ccbf3442 (excl.)
  • affected from dbef491ebe7f3a4fb1b9111878b86a426fd540b7 to 1ae134c012e10384cdac420b5cc6e0615cde0b55 (excl.)
  • affected from dbef491ebe7f3a4fb1b9111878b86a426fd540b7 to 5161e67c561c4f28a5d9335a6e859b02511de92b (excl.)
  • affected from dbef491ebe7f3a4fb1b9111878b86a426fd540b7 to 64d322c288577793eedd352b96ef75234ed380fe (excl.)
  • affected from dbef491ebe7f3a4fb1b9111878b86a426fd540b7 to 588d4a6795d99d080f74ef0b5f391ea8c453ae5d (excl.)
  • affected from dbef491ebe7f3a4fb1b9111878b86a426fd540b7 to d0f86fb36eb260abd10007b62c9dcc1028e03e61 (excl.)
Vendor Linux
Product Linux
Versions Default: affected
  • Version 4.6 is affected
  • unaffected from 0 to 4.6 (excl.)
  • unaffected from 5.10.265 to 5.10.* (incl.)
  • unaffected from 5.15.216 to 5.15.* (incl.)
  • unaffected from 6.1.183 to 6.1.* (incl.)
  • unaffected from 6.6.152 to 6.6.* (incl.)
  • unaffected from 6.12.104 to 6.12.* (incl.)
  • unaffected from 6.18.45 to 6.18.* (incl.)
  • unaffected from 7.1.9 to 7.1.* (incl.)
  • unaffected from 7.2 to * (incl.)

References