Information disclosure in Haproxy

CVE-2023-0836

An information leak vulnerability was discovered in HAProxy 2.1, 2.2 before 2.2.27, 2.3, 2.4 before 2.4.21, 2.5 before 2.5.11, 2.6 before 2.6.8, 2.7 before 2.7.1. There are 5 bytes left uninitialized in the connection buffer when encoding the FCGI_BEGIN_REQUEST record. Sensitive data may be disclosed to configured FastCGI backends in an unexpected way.

Vulnerability class: Information Disclosure

EPSS: 0.012 (65.0th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N.

Affected products

  • Haproxy — versions 2.1.0, 2.3.0, 2.7.0
  • N/a Haproxy — versions HAProxy 2.8, HAProxy 2.7.1, HAProxy 2.6.8, HAProxy 2.5.11, HAProxy 2.4.21, HAProxy 2.2.27

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2023-0836?
CVE-2023-0836 is a high-severity vulnerability in Haproxy, classified under Information Disclosure. CVSS score: 7.5/10. Published 2023-03-29.
How severe is CVE-2023-0836?
High severity. CVSS v3 base score is 7.5 out of 10.
Is CVE-2023-0836 known to be exploited?
1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.