Denial of Service Vulnerability in HAProxy by HAProxy Technologies
CVE-2026-110353

7.5HIGH

Key Information:

Vendor

Haproxy

Status
Haproxy
Haproxy Enterprise Edition
Kubernetes Ingress Controller
Kubernetes Ingress Controller Enterprise
Vendor
CVE Published:
22 October 2026

What is CVE-2026-110353?

A vulnerability in HAProxy prior to version 3.4.6 allows remote unauthenticated attackers to exploit a flaw in HTTP/2 PING frame processing. The function h2c_handle_ping fails to validate the size of read frames, which can lead to a scenario where partial frames cause significant CPU consumption. Attackers can open multiple connections with truncated frames, resulting in excessive CPU usage and ultimately a denial of service as the processing task remains unfulfilled. This situation persists until the HTTP request times out, impacting service availability.

Affected Version(s)

HAProxy 3.2.0 < 3.2.26

HAProxy 3.3.0 < 3.3.17

HAProxy 3.4.0 < 3.4.6

References

https://git.haproxy.org/?p=haproxy.git;a=commit;h=cec63e9...
vendor-advisory

CVSS V3.1

Score:
7.5
Severity:
HIGH
Confidentiality:
None
Integrity:
None
Availability:
None
Attack Vector:
Network
Attack Complexity:
Low
Privileges Required:
None
User Interaction:
None
Scope:
Unchanged

Timeline

  • Vulnerability published

  • Vulnerability Reserved

.