CVE-2026-110353

haproxy: HAProxy: Denial of Service via truncated HTTP/2 PING frame

Published Oct 22, 2026 CVSS 3.1 · 7.5 High EPSS < 1% KEV · Not listed
Description
HAProxy 3.2 before 3.4.6 allows a remote unauthenticated attacker to cause a denial of service (worker-thread CPU exhaustion) via a truncated HTTP/2 PING frame. h2c_handle_ping in src/mux_h2.c does not check for a short read, unlike the other H2 frame handlers. Because the incomplete frame cannot be processed, its data is never consumed, and the H2 multiplexer tasklet is repeatedly woken by that pending data without making progress. The CPU spins until timeout http-request closes the connection, and an attacker opening many such connections can sustain high CPU usage.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

Source ID Title
Ubuntu USN Ubuntu USN USN-8972-1 HAProxy vulnerabilities
History
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
Title Denial of Service via Truncated HTTP/2 PING in HAProxy haproxy: HAProxy: Denial of Service via truncated HTTP/2 PING frame
Weaknesses CWE-835
References
Metrics threat_severity

None

threat_severity

Important

Type Values Removed Values Added
First Time appeared Haproxy
Haproxy haproxy
Haproxy haproxy Enterprise
Haproxy kubernetes Ingress Controller
Haproxy kubernetes Ingress Controller Enterprise
Vendors & Products Haproxy
Haproxy haproxy
Haproxy haproxy Enterprise
Haproxy kubernetes Ingress Controller
Haproxy kubernetes Ingress Controller Enterprise
Type Values Removed Values Added
Title Denial of Service via Truncated HTTP/2 PING in HAProxy
Type Values Removed Values Added
Description HAProxy 3.2 before 3.4.6 allows a remote unauthenticated attacker to cause a denial of service (worker-thread CPU exhaustion) via a truncated HTTP/2 PING frame. h2c_handle_ping in src/mux_h2.c does not check for a short read, unlike the other H2 frame handlers. Because the incomplete frame cannot be processed, its data is never consumed, and the H2 multiplexer tasklet is repeatedly woken by that pending data without making progress. The CPU spins until timeout http-request closes the connection, and an attacker opening many such connections can sustain high CPU usage.
Weaknesses CWE-252
References
Metrics cvssV3_1

{'score': 7.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
mitre
Published
Updated
Oct 22, 2026, 7:10 PM
Reserved
Oct 13, 2026, 11:18 PM
Status
Awaiting Analysis
Published
Oct 22, 2026, 3:16 AM
Modified
Oct 22, 2026, 7:17 PM
Severity
Important
Public date
Oct 22, 2026, 2:53 AM