Auth-bypass in widely used HAProxy Data Plane API enables full admin access and config replacement; impacts infrastructure management across organizations.
CVE-2026-109575
Auth bypass in HAProxy Data Plane API allows unauthenticated full admin access.
Is CVE-2026-109575 being exploited?
Not confirmed. CVE-2026-109575 does not appear in CISA's Known Exploited Vulnerabilities catalog, which records only exploitation that has been observed and reported publicly. That is evidence of absence of a report, not evidence the flaw is unattacked. EPSS currently estimates a 0.36% probability of exploitation in the next 30 days.
How severe is CVE-2026-109575?
CVE-2026-109575 is rated Critical with a CVSS score of 9.8. Severity describes how bad exploitation would be, not how likely it is: pair it with exploitation evidence before deciding what to patch first.
Is there a patch for CVE-2026-109575?
Yes. A fix has been recorded for CVE-2026-109575. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-109575 affect?
CVE-2026-109575 affects HAProxy Data Plane API 2.2.0 through 3.4.3, Corresponding HAProxy Enterprise Edition releases. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-109575?
Upgrade to fixed versions (>=3.4.4, 3.3.9, 3.2.17, 3.0.25, 2.9.29) and restrict management access.
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Unauthenticated attacker can bypass auth on HTTP/UNIX management endpoints to gain full API admin rights, read or replace HAProxy config.
Immediate action required
- affected>= 2.2.0 and <= 2.9.28
- affected>= 3.0.0 and <= 3.0.24
- affected>= 3.1.0 and <= 3.2.16
- affected>= 3.3.0 and <= 3.3.8
- affected>= 3.4.0 and <= 3.4.3
- affected>= 2.2.0-ee1 and <= 2.9.28-ee1
- affected>= 3.0-ee and <= 3.0.24-ee1
- affected>= 3.1-ee and <= 3.2.16-ee1
- affected>= 3.3-ee and <= 3.3.8-ee1
- affected>= 3.4-ee and <= 3.4.3-ee2
As published in the CVE Program record. A version outside these ranges is not a statement that it is unaffected — vendors sometimes understate a range, and distribution-backported builds carry upstream numbers that do not reflect what was patched into them.