CVE intelligence

CVE-2026-80738

Vulnerability intelligence

Published Sep 3, 2026Sources checked Oct 28, 2026

7.3HIGHCVSS out of 10

What this means

Review the available evidence

CVE-2026-80738 and is rated High severity with a CVSS score of 7.3. It is not in the current CISA KEV record we collected. That does not prove exploitation has not occurred.

What to do next

Remediation and response

Microsoft Security Response Center guidance

Vendor revision: Sep 24, 2026

Release Notes

CISA KEVNot listedBased on the latest collected catalog

EPSS0.2%Estimated 30-day exploitation probability

Ransomware useNot markedCISA KEV ransomware field

Threat actors0Source-linked actor relationships

Overview

What is 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.

Source: NVD