AUGUST 28, 2026
Live Feed
Back to database
Case File

CVE-2026-55203

HIGH · CVSS 7.5 EPSS 0.35% Public Exploit

Source: NVD + CISA KEV + EPSS (historical backfill) · Published 2026-06-18 · Last synced 2026-08-04

CyberRota Analysis

This is a high severity vulnerability with a CVSS score of 7.5. Public exploit code or proof-of-concept references have been detected in its references.

Public Exploit Signal

A public exploit, PoC, GitHub repository or Metasploit reference was detected for this CVE.

GitHub PoC Links

Note: these links are listed for security research and verification purposes only.

CVE
CVE-2026-55203
Severity
HIGH
CVSS
7.5
EPSS
0.35%

Original NVD Description

HAProxy through 3.4.0, fixed in commit 5985276, contains an integer overflow vulnerability in the fcgi_conn structure's drl field that allows buffer misparse as new FCGI record headers. When contentLength is 65535 and paddingLength is 1 or more, the drl field wraps to 0, causing incorrect record consumption and allowing malicious FastCGI backends to desynchronize the FCGI framing parser, potentially causing request routing errors, response smuggling, or memory safety issues.

Related CVEs

Other vulnerabilities affecting the same vendor(s)