SB20260816236 - Out-of-bounds read in Linux kernel net vxlan driver

Description

This security bulletin contains information about 1 vulnerability.

1) Out-of-bounds read (CVE-ID: CVE-2026-74473)

CWE-ID: CWE-125 - Out-of-bounds read

CVSSv4: 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]

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

The vulnerability exists due to an out-of-bounds read in route_shortcircuit() in drivers/net/vxlan/vxlan_core.c when processing packets with a non-linear buffer layout. A remote attacker can send a specially crafted packet to cause a denial of service.

The issue occurs because the network header may not be fully pulled into the linear buffer before ip_hdr(skb)->daddr or ipv6_hdr(skb)->daddr is dereferenced.

Remediation

Install update from vendor's website.

References

• https://git.kernel.org/stable/c/26bb2dd0a8839617e2c79ffbbe1923f8e4bab9fb
• https://git.kernel.org/stable/c/42887be7c4cf283cce02cd0fb6411221167c8b6c
• https://git.kernel.org/stable/c/4f3f96e771a20263635bb5e1307c112d613b4bbd
• https://git.kernel.org/stable/c/aa0d31376d574ac858a40078431a77127bf04ee4
• https://git.kernel.org/stable/c/ee799977d7941dbfb11049e17edd9eaf4f8820f7