CVE-2026-55203: HAProxy - Integer Overflow in FCGI Demux Record Length Field

Overview

Severity

High (CVSS 7.5)

CVSS Vector

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

Exploit Status

Not Exploited

Patch Tuesday

2026-Jun

Released

2026-06-27

EPSS Score

0.32% (percentile: 23.9%)

Affected Products (1)

Other

• 21468-17084

Revision History

• 2026-06-27: Information published.