SECURELYN

CVE-2026-109575

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.RequireAndVeri…

Scores

9.8
CVSS 9.8 out of 10, critical severity.
0.4%
EPSS 0.4% chance of exploitation in the next 30 days.

The facts

Published
12 October 2026
Last changed
16 October 2026
NVD status
Awaiting Analysis
Severity
Critical, CVSS 9.8 out of 10 (version 3.1)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Weakness
Known exploited
Not in the CISA Known Exploited Vulnerabilities catalogue in this build.
EPSS
0.4% chance of exploitation activity in the next 30 days (percentile 28).

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References