CVE-2025-11230 Denial of service vulnerability in HAProxy mjson library
High 7.5
Published
Updated
Check this codebase for CVE-2025-11230 and fix it if it is affected.
What it is: CVE-2025-11230 is a high-severity denial of service vulnerability in HAProxy Community Edition, published on 19 Nov 2025. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2025-11230 in the wild and no public exploit code.
Affected packages and fixed versions:
- haproxy (Bitnami): affected from 2.4.0; fixed in 2.4.30, 2.6.23, 2.8.16, 3.0.12, 3.1.9, 3.2.6
Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.
Reference: https://insights.sbomify.com/CVE-2025-11230/ (Markdown: https://insights.sbomify.com/CVE-2025-11230/index.md)
Remote attackers can cause denial of service in HAProxy by sending specially crafted JSON requests due to inefficient algorithm complexity in the mjson library.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2025-11230?
CVE-2025-11230 is a high-severity denial of service vulnerability in HAProxy Community Edition, published on 19 Nov 2025. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
Inefficient algorithm complexity in mjson in HAProxy allows remote attackers to cause a denial of service via specially crafted JSON requests.
Weakness: CWE-407
Which versions are affected by CVE-2025-11230?
1 open source package ship an affected version, including haproxy. It affects 4 products.
| Package | Affected | Fixed in |
|---|---|---|
haproxy Bitnami | From 2.4.0 | 2.4.30, 2.6.23, 2.8.16, 3.0.12, 3.1.9, 3.2.6 |
Linux distribution packages (39)
haproxy AlmaLinux:10 | All versions | 3.0.5-4.el10_1.1 |
haproxy AlmaLinux:9 | All versions | 2.8.14-1.el9_7.1 |
haproxy Red Hat:enterprise_linux:10.1 | All versions | 0:3.0.5-4.el10_1.1 |
haproxy-debuginfo Red Hat:enterprise_linux:10.1 | All versions | 0:3.0.5-4.el10_1.1 |
haproxy-debugsource Red Hat:enterprise_linux:10.1 | All versions | 0:3.0.5-4.el10_1.1 |
haproxy Red Hat:enterprise_linux:9::appstream | All versions | 0:2.8.14-1.el9_7.1 |
haproxy-debuginfo Red Hat:enterprise_linux:9::appstream | All versions | 0:2.8.14-1.el9_7.1 |
haproxy-debugsource Red Hat:enterprise_linux:9::appstream | All versions | 0:2.8.14-1.el9_7.1 |
haproxy Red Hat:enterprise_linux_eus:10.0 | All versions | 0:3.0.5-4.el10_0.1 |
haproxy-debuginfo Red Hat:enterprise_linux_eus:10.0 | All versions | 0:3.0.5-4.el10_0.1 |
haproxy-debugsource Red Hat:enterprise_linux_eus:10.0 | All versions | 0:3.0.5-4.el10_0.1 |
haproxy Red Hat:hummingbird:1 | All versions | 0:3.0.19-1.hum1 |
haproxy Red Hat:rhel_e4s:9.0::appstream | All versions | 0:2.4.7-2.el9_0.3 |
haproxy-debuginfo Red Hat:rhel_e4s:9.0::appstream | All versions | 0:2.4.7-2.el9_0.3 |
haproxy-debugsource Red Hat:rhel_e4s:9.0::appstream | All versions | 0:2.4.7-2.el9_0.3 |
haproxy Red Hat:rhel_e4s:9.2::appstream | All versions | 0:2.4.17-6.el9_2.3 |
haproxy-debuginfo Red Hat:rhel_e4s:9.2::appstream | All versions | 0:2.4.17-6.el9_2.3 |
haproxy-debugsource Red Hat:rhel_e4s:9.2::appstream | All versions | 0:2.4.17-6.el9_2.3 |
haproxy Red Hat:rhel_eus:9.4::appstream | All versions | 0:2.4.22-3.el9_4.1 |
haproxy-debuginfo Red Hat:rhel_eus:9.4::appstream | All versions | 0:2.4.22-3.el9_4.1 |
haproxy-debugsource Red Hat:rhel_eus:9.4::appstream | All versions | 0:2.4.22-3.el9_4.1 |
haproxy Red Hat:rhel_eus:9.6::appstream | All versions | 0:2.4.22-4.el9_6.1 |
haproxy-debuginfo Red Hat:rhel_eus:9.6::appstream | All versions | 0:2.4.22-4.el9_6.1 |
haproxy-debugsource Red Hat:rhel_eus:9.6::appstream | All versions | 0:2.4.22-4.el9_6.1 |
haproxy Rocky Linux:10 | All versions | 0:3.0.5-4.el10_1.1 |
haproxy Rocky Linux:9 | All versions | 0:2.8.14-1.el9_7.1 |
haproxy SUSE:Linux Enterprise High Availability Extension 15 SP4 | All versions | 2.4.22+git0.f8e3218e2-150400.3.25.1 |
haproxy SUSE:Linux Enterprise High Availability Extension 15 SP5 | All versions | 2.4.22+git0.f8e3218e2-150400.3.25.1 |
haproxy SUSE:Linux Enterprise High Availability Extension 15 SP6 | All versions | 2.8.11+git0.01c1056a4-150600.3.9.1 |
haproxy SUSE:Linux Enterprise High Availability Extension 15 SP7 | All versions | 2.8.11+git0.01c1056a4-150600.3.9.1 |
haproxy SUSE:Linux Enterprise High Availability Extension 16.0 | All versions | 3.2.0+git0.e134140d2-160000.3.1 |
haproxy SUSE:Linux Enterprise Micro 5.3 | All versions | 2.4.22+git0.f8e3218e2-150400.3.25.1 |
haproxy SUSE:Linux Enterprise Micro 5.4 | All versions | 2.4.22+git0.f8e3218e2-150400.3.25.1 |
haproxy SUSE:Linux Enterprise Micro 5.5 | All versions | 2.4.22+git0.f8e3218e2-150400.3.25.1 |
haproxy SUSE:Linux Enterprise Server for SAP applications 16.0 | All versions | 3.2.0+git0.e134140d2-160000.3.1 |
haproxy SUSE:Linux Micro 6.0 | All versions | 2.8.11+git0.01c1056a4-2.1 |
haproxy SUSE:Linux Micro 6.1 | All versions | 2.8.11+git0.01c1056a4-slfo.1.1_2.1 |
haproxy SUSE:Linux Micro 6.2 | All versions | 3.2.0+git0.e134140d2-160000.3.1 |
haproxy openSUSE:Leap 15.6 | All versions | 2.8.11+git0.01c1056a4-150600.3.9.1 |
Products include Haproxy Aloha Appliance, Haproxy Haproxy, Haproxy Haproxy Enterprise, Haproxy Kubernetes Ingress Controller.
How do I fix CVE-2025-11230?
Upgrade haproxy to a fixed version for your release line: 2.4.30, 2.6.23, 2.8.16 or 3.0.12.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2025-11230 being exploited?
There is no known exploitation of CVE-2025-11230 in the wild and no public exploit code.
Sources
Also known as ALSA-2025:21691, ALSA-2025:21693, AZL-70538, AZL-70583, BIT-haproxy-2025-11230, CLSA-2025-1764324159 and 37 more.