CVE-2026-80585: mptcp: fastopen: only mark MPTFO subflows with SYN data

Overview

Severity

Low (CVSS 3.7)

CVSS Vector

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

Exploit Status

Not Exploited

Patch Tuesday

2026-Aug

Released

2026-08-27

EPSS Score

0.32% (percentile: 24.1%)

Affected Products (1)

Other

• 21684-17084

Revision History

• 2026-08-27: Information published.