CVE-2026-109575

Received
Published: 12 Oct 2026, 19:32
Last modified:12 Oct 2026, 19:36

Vulnerability Summary

Overall Risk (default)
high
70/100
CVSS Score
9.8 CRITICAL
v3.1 (cve.org)
EPSS Score
No data
KEV
Not listed
Ransomware
No reports
Public exploits
None found
Dark Web
Not detected

Timeline

12 Oct 2026, 19:32
Published
Vulnerability first disclosed
12 Oct 2026, 19:36
Last Modified
Vulnerability information updated

Description

In HAProxy Data Plane API 2.2.0 through 3.4.3 (and corresponding Enterprise Edition releases), Server.ConfigureAPI() has process-global authentication logic that improperly drops security controls across multiple transport types. When a TLS Certificate Authority (tls_ca) is configured and a numeric TLS port (tls_port) is specified, the application globally disables Basic authentication on its shared internal request handler. Because this handler is shared concurrently among HTTP, HTTPS, and UNIX domain socket listeners, and mutual TLS (mTLS) client certificate verification (tls.RequireAndVerifyClientCert) is enforced exclusively on the HTTPS server path, all other simultaneously active non-mTLS listeners fail open. Consequently, an unauthenticated attacker capable of reaching an affected HTTP or UNIX management endpoint can completely bypass credentials to gain full API administrative access. This allows unauthorized remote or local actors to read sensitive, cleartext HAProxy configuration data or replace the managed configuration entirely via the raw configuration endpoint. This has been fixed in versions 3.4.4, 3.3.9, 3.2.17, 3.0.25, 2.9.29, and their respective EE backports by migrating to a per-request TLS connection-state validation model.

CVSS Metrics

  • v3.1•CRITICAL•Score: 9.8CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Techniques & Countermeasures

  • CWE-306•Missing Authentication for Critical Function

    The product does not perform any authentication for functionality that requires a provable user identity or consumes a significant amount of resources.

Affected Systems

  • haproxy•data plane api ce

    ≥ 2.2.0, ≤ 2.9.28 | ≥ 3.0.0, ≤ 3.0.24 | ≥ 3.1.0, ≤ 3.2.16 | ≥ 3.3.0, ≤ 3.3.8 | ≥ 3.4.0, ≤ 3.4.3

  • haproxy•data plane api ee

    ≥ 2.2.0-ee1, ≤ 2.9.28-ee1 | ≥ 3.0-ee, ≤ 3.0.24-ee1 | ≥ 3.1-ee, ≤ 3.2.16-ee1 | ≥ 3.3-ee, ≤ 3.3.8-ee1 | ≥ 3.4-ee, ≤ 3.4.3-ee2

References (4)