Out-of-bounds read in Linux kernel - CVE-2026-72417

Vulnerability identifier: #VU143022

CSH Severity: Medium

CVSS v4: 8.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]

CVE-ID: CVE-2026-72417

CWE-ID: CWE-125

Exploitation vector: Remote access

Exploit availability: No public exploit available

The vulnerability allows a remote attacker to cause a denial of service.

The vulnerability exists due to an out-of-bounds access in nf_flow_ip4_tunnel_proto() when processing malformed IP headers. A remote attacker can send a specially crafted packet to cause a denial of service.

Linux kernel
Ubuntu
linux (Ubuntu package)
linux-gcp (Ubuntu package)

Install security update from vendor's repository.

Linux kernel - update to 7.0 rc3
linux (Ubuntu package) - addressed in versions 7.0.0-34.34, 7.0.0-34.34.1, 7.0.0-34.34~24.04.1, 7.0.0-1012.12~24.04.1, 7.0.0-1013.13, 7.0.0-1013.13~24.04.1, 7.0.0-1014.14, 7.0.0-1020.20
linux-gcp (Ubuntu package) - addressed in versions 7.0.0-1013.13, 7.0.0-1013.13~24.04.1, 7.0.0-1014.14

• https://git.kernel.org/stable/c/025a41e76b51fbc7b8eaa5bacbaa9621d00e6aa7
• https://git.kernel.org/stable/c/84460b644329e25809b4a6d9279d6359d7fd8ebc

• Out-of-bounds read in Linux kernel netfilter
• Ubuntu update for linux-gcp
• Ubuntu update for linux