How severe is CVE-2024-21536?

No CVSS score has been assigned to CVE-2024-21536 yet. Review the advisory details and affected package list to assess your exposure.

Which packages are affected by CVE-2024-21536?

CVE-2024-21536 affects the following packages: http-proxy-middleware (npm), http-proxy-middleware (npm). Ecosystems affected: npm.

How do I fix CVE-2024-21536?

Update http-proxy-middleware to 2.0.7 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2024-21536 is resolved across your whole dependency graph.

How do I detect CVE-2024-21536 in my npm dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for http-proxy-middleware, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

How do I mitigate CVE-2024-21536 if there is no patch (or I can't update yet)?

Cap what an attacker can consume: apply request size, rate and timeout limits in front of the affected component, and run it with memory and CPU limits so exhaustion degrades one worker rather than the whole service.

Is CVE-2024-21536 actively exploited in the wild?

Yes. There are 1 known exploit references for CVE-2024-21536, including 1 in-the-wild exploitation observed on GitHub and other sources. Treat this as actively exploitable and prioritize patching immediately. All exploit code should only be run in an isolated sandbox environment for research or authorized testing — never against production systems without explicit written authorization.

What is the EPSS score for CVE-2024-21536?

CVE-2024-21536 has an EPSS (Exploit Prediction Scoring System) score of 1.0%, placing it in the 64th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

What type of vulnerability is CVE-2024-21536?

CVE-2024-21536 is classified as Uncontrolled Resource Consumption (CWE-400). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was CVE-2024-21536 published, and has it been updated?

CVE-2024-21536 was published on October 19, 2024 and was last updated on October 28, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

📦 npm

Not in CISA KEV

CVE-2024-21536 — http-proxy-middleware

Fix: chimurai/http-proxy-middleware@0b4274e

CVE-2024-21536 is a Uncontrolled Resource Consumption vulnerability in http-proxy-middleware. 1 public exploit or proof-of-concept reference is indexed, so weaponization risk is real. A fix is available for http-proxy-middleware — see the affected versions and patch details below.

Denial of service in http-proxy-middleware

Also known asGHSA-c7qv-q95q-8v27

Published

Oct 19, 2024

Updated

Oct 28, 2026

Affected

2 pkgs

Patched

2 / 2

Exploits

1 known

Exploitation data as of Nov 3, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

Exploitation Status

Proof-of-concept exploit code exists

CISA’s SSVC triage found public proof-of-concept exploit code for this CVE, though no confirmed active exploitation.
CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.

Exploitation and automatability from CISA’s SSVC triage for CVE-2024-21536.

EPSS Exploitation Probability

via FIRST.org ↗

1.0%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs64th percentile — riskier than 64% of all scored CVEsHighest risk

Probability of exploitation in the next 30 days, from FIRST.org EPSS.

Real-World Exposure

2 pkgs affected

How broadly this vulnerability is actually deployed: weekly install volume shows current usage, and reverse-dependency count shows how many other packages break if it stays unpatched.

5Kother npm packages depend on this — each one inherits the vulnerability until it's patched upstream

http-proxy-middlewarenpm

31.5Mdownloads / week

Description

Versions of the package http-proxy-middleware before 2.0.7, from 3.0.0 and before 3.0.3 are vulnerable to Denial of Service (DoS) due to an UnhandledPromiseRejection error thrown by micromatch. An attacker could kill the Node.js process and crash the server by making requests to certain paths.

Affected Packages

2 total 2 fixed

Ecosystem	Package	Vulnerable range	Fix
📦npm	`http-proxy-middleware`	all versions	2.0.7`npm install http-proxy-middleware@2.0.7`
📦npm	`http-proxy-middleware`	≥ 3.0.0&&< 3.0.3	3.0.3`npm install http-proxy-middleware@3.0.3`

Affected Products

1 product · 2 configurations

Application

http-proxy-middlewarechimurai

≥ 3.0.0 && < 3.0.3

range

Exploits & PoCs

Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.

Versions of the package http-proxy-middleware before 2.0.7, from 3.0.0 a…

gist.github.comNVDNov 2024

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for http-proxy-middleware, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update http-proxy-middleware to 2.0.7 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2024-21536 is resolved across your whole dependency graph.
Workarounds
Cap what an attacker can consume: apply request size, rate and timeout limits in front of the affected component, and run it with memory and CPU limits so exhaustion degrades one worker rather than the whole service.

Fixing This On Your OS

If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project.

Red HatModerate

This vulnerability is rated with a Moderate impact for Red Hat products because an unauthenticated remote request can terminate the backend Node.js process, yet it does not compromise data confidentiality or system integrity. In typical Red Hat environments such as OpenShift container platforms and web consoles,…

Workaround published by Red Hat

Red Hat Product Security does not have any mitigation recommendations at this time.

Source: Red Hat security advisory for CVE-2024-21536 (CC BY 4.0)

Product	Fixed in	Advisory
Discovery 1 for RHEL 9	`discovery/discovery-server-rhel9:1.12.0-1`	RHSA-2025:1249
Red Hat Advanced Cluster Security 4.5	`advanced-cluster-security/rhacs-central-db-rhel8:4.5.9-1`	RHSA-2025:3928
Red Hat Advanced Cluster Security 4.6	`advanced-cluster-security/rhacs-central-db-rhel8:4.6.5-1`	RHSA-2025:3929
Red Hat Advanced Cluster Security 4.7	`advanced-cluster-security/rhacs-central-db-rhel8:4.7.2-2`	RHSA-2025:3930
Red Hat Developer Hub 1.3 on RHEL 9	`rhdh/rhdh-hub-rhel9:1.3-124`	RHBA-2024:9054
Red Hat Migration Toolkit for Containers 1.8	`rhmtc/openshift-migration-ui-rhel8:v1.8.7-2`	RHSA-2025:8510
Red Hat OpenShift Service Mesh 2.6 for RHEL 8	`openshift-service-mesh/grafana-rhel8:2.6.3-2`	RHSA-2024:9627
RHODF-4.14-RHEL-9	`odf4/ocs-client-console-rhel9:v4.14.18-2`	RHSA-2025:8551

Frequently Asked Questions

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