CVE-2026-80738

high

Description

In the Linux kernel, the following vulnerability has been resolved: bpf: Check sk_state before sk_protocol in bpf_tcp_*_syncookie bpf_tcp_gen_syncookie and bpf_tcp_check_syncookie accept a socket pointer 'sk' with argument type ARG_PTR_TO_BTF_ID_SOCK_COMMON. However, they access sk->sk_protocol without validating whether 'sk' represents a full socket. Fix this issue by checking sk->sk_state != TCP_LISTEN before inspecting sk->sk_protocol in both bpf_tcp_gen_syncookie and bpf_tcp_check_syncookie. Since mini-sockets are never in the TCP_LISTEN state, the condition short-circuits and prevents dereferencing fullsock-specific fields.

References

https://git.kernel.org/stable/c/31a420a822ff92e2090bd5d65efe8e34e2d6d9b8

https://git.kernel.org/stable/c/23f682083aa3fbc0c49667818efd6979a8bc5ac2

Details

Source: Mitre, NVD

Published: 2026-09-03

Updated: 2026-09-04

Risk Information

CVSS v2

Base Score: 6.4

Vector: CVSS2#AV:L/AC:L/Au:S/C:C/I:C/A:P

Severity: Medium

CVSS v3

Base Score: 7.3

Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:L

Severity: High

EPSS

EPSS: 0.00198