7.5

CVE-2023-0836: haproxy

CVSS: 7.5v3.1HighModified
AliasesRHSA-2023:6496UBUNTU-CVE-2023-0836USN-5994-1
Published 29-03-2023Last modified 18-02-2025
Open JSON

Vulnerability summary

CVE-2023-0836 is a high (CVSS 7.5) vulnerability in haproxy. EPSS estimates a 1.20% chance of exploitation in the next 30 days, higher than 67.9% of scored vulnerabilities.

Overall risk
30/100
0100
Medium · default modelHow is this calculated?
CVSS score
7.5/10
010
High · v3.1 (CVE.org)
EPSS score
1.20%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Timeline

  1. 29-03-2023
    PublishedVulnerability first disclosed.
  2. 18-02-2025
    Last modifiedVulnerability information updated.

Description

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.

CVSS metrics

5 scores · 5 sources · 1 version

EPSS trend

Probability

1.20%

Chance of exploitation in the next 30 days

Percentile

68%

Versus all other CVEs

30-day change

0.00 pp

From 1.20% on 21-09-2026

21-09-202621-10-2026
EPSS score
1.20%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Redhat3 products
  • haproxy< 0:2.4.22-1.el9
  • haproxy-debuginfo< 0:2.4.22-1.el9
  • haproxy-debugsource< 0:2.4.22-1.el9
Debian1 product
  • haproxy< 2.2.9-2+deb11u5 | < 2.6.8-1
Haproxy1 product
  • haproxyEOL≥ 2.2.0, < 2.2.27 | ≥ 2.4.0, ≤ 2.4.21 | ≥ 2.5.0, ≤ 2.5.11 | ≥ 2.6.0, ≤ 2.6.8 | 2.1.0 | 2.3.0 | 2.7.0
Ubuntu1 product
  • haproxy< 2.4.18-0ubuntu1.3

4 vendors · 6 products

References

16 links
Show all 16 references