CVE-2026-109575 HAProxy Data Plane API - Authentication Bypass

HAProxy Data Plane API 2.2.0 through 3.4.3 contains a broken authentication caused by process-global authentication logic improperly dropping security controls across multiple transport types, letting unauthenticated attackers bypass credentials and gain full API administrative access, exploit requires attacker to reach HTTP or UNIX management endpoints.

CVSS base score 9.8 /10
Critical
CISA KEV
Not listed
Public exploit
None known
Authentication
Not required
EPSS
0.36% chance of exploitation in 30 days
View the NVD record ↗

Details

Type
Authentication Bypass
Impact
Broken Authentication
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Published
12 October 2026
Updated
15 October 2026
Weakness
CWE-306

Vendor fix

Update to versions 3.4.4, 3.3.9, 3.2.17, 3.0.25, 2.9.29 or later.

Patching closes this CVE. It does not tell you which of your systems run the affected version, or what else is exposed alongside them.

References

← All CVEs