Cyber Resilience

CVE-2025-11230

DoS in Haproxy Enterprise 2.4r1 … 3.1r1

Published
19 November 2025
Modified
19 December 2025
Patch / advisory
CVSS Score v3.1 7.5
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS Score 0.0070 50th percentile
Risk Priority 58 floored blend · peak EPSS

Summary

CVE-2025-11230 is a high-severity Inefficient Algorithmic Complexity (CWE-407) vulnerability in Haproxy Haproxy Enterprise. Its CVSS base score is 7.5 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Endpoint Denial of Service (T1499); ranked at the 50th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

The strongest mitigations our analysis identified map to SC-5 (Denial-of-service Protection) and SC-6 (Resource Availability) — see the control section below for these in your framework.

EU & UK References

Vulnerability Data

Inefficient algorithm complexity in mjson in HAProxy allows remote attackers to cause a denial of service via specially crafted JSON requests.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise Techniques

T1499 Endpoint Denial of Service Impact
Adversaries may perform Endpoint Denial of Service (DoS) attacks to degrade or block the availability of services to users.
T1499.003 Application Exhaustion Flood Impact
Adversaries may target resource intensive features of applications to cause a denial of service (DoS), denying availability to those applications.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2024-45506Same product: Haproxy Haproxy
CVE-2026-55204Same product: Haproxy Haproxy
CVE-2024-21909Shared CWE-407
CVE-2023-45539Same product: Haproxy Haproxy
CVE-2023-4408Shared CWE-407
CVE-2025-67841Shared CWE-407
CVE-2026-44378Shared CWE-407
CVE-2026-59869Shared CWE-407
CVE-2024-8177Shared CWE-407
CVE-2026-33555Same product: Haproxy Haproxy

Affected Assets

haproxy
aloha appliance
14.5.0 — 14.5.33 · 15.5.0 — 15.5.28 · 16.5.0 — 16.5.19
haproxy
haproxy
2.4.0 — 2.4.30 · 2.6.0 — 2.6.23 · 2.8.0 — 2.8.16
haproxy
haproxy enterprise
2.4r1, 2.6r1, 2.8r1, 3.0r1, 3.1r1
haproxy
kubernetes ingress controller
≤ 1.9.14-ee7 · ≤ 3.1.12 · 1.10.10-ee1 — 1.11.12-ee10

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

Detect
Catch it (NIST detect / respond)

Harden
Shrink the surface (DISA STIG)

Validate
Prove the fix (OWASP ASVS)
  • V1.2.9

Mitigating Controls (NIST 800-53 r5) AI

Denial-of-service protection directly reduces the impact of resource exhaustion triggered by worst-case algorithmic inputs.

Resource availability allocation limits blast radius when an inefficient algorithm is forced into its worst case.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.PS-06 mostly match
prevents

Secure SDLC practices (code review, complexity analysis, safe algorithm selection) prevent introduction of exploitable worst-case behavior.

DE.CM-09 partial match
prevents

Runtime monitoring of software and resources can detect the performance impact of triggered worst-case complexity.

ID.RA-01 partial match
prevents

Identifying and recording algorithmic-complexity vulnerabilities directly addresses the root cause before exploitation.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

finds

Security testing can uncover performance issues stemming from algorithmic complexity.

mitigates

Redundancy of processing facilities can absorb resource exhaustion from inefficient algorithms.

finds

Monitoring activities can identify anomalous resource consumption indicative of algorithmic complexity attacks.

prevents

Secure development life cycle includes design reviews that can catch inefficient algorithms before deployment.

prevents

Secure system architecture principles encourage selection of algorithms with acceptable worst-case complexity.

prevents

Secure coding practices can include guidelines to avoid or mitigate inefficient algorithms.

References