CVE-2026-80738

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.

CVSS v3 7.3 HIGH

7.3^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.8 / Impact : 5.5

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://git.kernel.org/stable/c/23f682083aa3fbc0c49667818efd6979a8bc5ac2
https://git.kernel.org/stable/c/31a420a822ff92e2090bd5d65efe8e34e2d6d9b8

Configurations

No configuration.

History

No history.

Information

Published : 2026-09-03 13:06

Updated : 2026-09-04 05:17

NVD link : CVE-2026-80738

Mitre link : CVE-2026-80738

CVE.ORG link : CVE-2026-80738

JSON object : View

Products Affected

No product.

CWE

No CWE.

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