How severe is CVE-2023-26044?

CVE-2023-26044 has a CVSS score of 5.3/10, rated MEDIUM. Review your exposure and patch according to your risk tolerance.

Which packages are affected by CVE-2023-26044?

CVE-2023-26044 affects the following packages: react/http (Packagist). Ecosystems affected: Packagist.

How do I fix CVE-2023-26044?

Update react/http to 1.9.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2023-26044 is resolved across your whole dependency graph.

How do I detect CVE-2023-26044 in my Packagist dependencies?

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

How do I mitigate CVE-2023-26044 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-2023-26044 actively exploited in the wild?

No public exploit code has been indexed for CVE-2023-26044 yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for CVE-2023-26044?

CVE-2023-26044 has an EPSS (Exploit Prediction Scoring System) score of 0.7%, placing it in the 53th 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-2023-26044?

CVE-2023-26044 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-2023-26044 published, and has it been updated?

CVE-2023-26044 was published on May 17, 2023 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.

🐘

🐘 Packagist

Not in CISA KEV

MEDIUM severity

CVE-2023-26044 — http

MEDIUMFix: reactphp/http@9681f76

CVE-2023-26044 is a medium-severity (CVSS 5.3) Uncontrolled Resource Consumption vulnerability in react/http. A fix is available for react/http — see the affected versions and patch details below.

ReactPHP's HTTP server continues parsing unused multipart parts after reaching limits

Also known asGHSA-95x4-j7vc-h8mf

Published

May 17, 2023

Updated

Oct 28, 2026

Affected

1 pkg

Patched

1 / 1

Exploits

None indexed

Exploitation data as of Nov 7, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

Exploitation Status

No confirmed exploitation observed yet

CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.

Exploitation and automatability from CISA’s SSVC triage for CVE-2023-26044.

EPSS Exploitation Probability

via FIRST.org ↗

0.7%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs53th percentile — riskier than 53% of all scored CVEsHighest risk

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

How urgent is this, really

Where this sits among everything scored

Real-World Exposure

1 pkg affected

🐘react/http

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects Packagist packages — download data is not available via public APIs for these ecosystems.

Description

Summary

Previous versions of ReactPHP's HTTP server component contain a potential DoS vulnerability that can cause high CPU load when processing large HTTP request bodies. This vulnerability has little to no impact on the default configuration, but can be exploited when explicitly using the RequestBodyBufferMiddleware with very large settings. This might lead to consuming large amounts of CPU time for processing requests and significantly delay or slow down the processing of legitimate user requests.

Patches

The supplied patch resolves this vulnerability for ReactPHP.

Workarounds

Keeping the request body limit using RequestBodyBufferMiddleware sensible will mitigate it.
Infrastructure or DevOps can place a reverse proxy in front of the ReactPHP HTTP server to filter out any excessive HTTP request bodies.

References

A similar vulnerability was discovered in PHP recently, see also PHP's security advisory (CVE-2023-0662). The fix is based on the PHP-FPM fix.

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
🐘Packagist	`react/http`	≥ 0.8.0&&< 1.9.0	1.9.0`composer require react/http:^1.9.0`

Affected Products

1 product · 1 configurations

Application

httpreactphp

≥ 0.8.0 && < 1.9.0

range

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for react/http, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update react/http to 1.9.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2023-26044 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.

Frequently Asked Questions

### Summary Previous versions of ReactPHP's HTTP server component contain a potential DoS vulnerability that can cause high CPU load when processing large HTTP request bodies. This vulnerability has little to no impact on the default configuration, but can be exploited when explicitly using the `RequestBodyBufferMiddleware` with very large settings. This might lead to consuming large amounts of CPU time for processing requests and significantly delay or slow down the processing of legitimate user requests. ### Patches The supplied patch resolves this vulnerability for ReactPHP. ### Workar