# CVE-2023-26044: ReactPHP's HTTP server continues parsing unused multipart parts after reaching limits

> Attackers can cause high CPU load and service delays by sending large HTTP bodies when specific middleware is configured with high limits.

- **Severity:** Medium 5.3 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 17 May 2023
- **Updated:** 23 Jan 2025
- **Also known as:** GHSA-95x4-j7vc-h8mf, UBUNTU-CVE-2023-26044

## What is CVE-2023-26044?

CVE-2023-26044 is a medium-severity denial of service vulnerability in reactphp http, published on 17 May 2023. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

react/http is an event-driven, streaming HTTP client and server implementation for ReactPHP.  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. This issue has been addressed in release 1.9.0. Users are advised to upgrade. Users unable to upgrade may keep the request body limited using RequestBodyBufferMiddleware with a sensible value which should mitigate the issue. An infrastructure or DevOps workaround could be to place a reverse proxy in front of the ReactPHP HTTP server to filter out any excessive HTTP request bodies.

Weakness: CWE-400 (Uncontrolled Resource Consumption)

## Which versions are affected by CVE-2023-26044?

2 open source packages ship an affected version, including react/http. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `react/http` | Packagist | From 0.8.0 | 1.9.0 |
| `react/http` | Packagist | From 0.8.0 | 1.9.0 |

Products: Reactphp Http.

## How do I fix CVE-2023-26044?

Upgrade react/http to 1.9.0 or later.

## Is CVE-2023-26044 being exploited?

There is no known exploitation of CVE-2023-26044 in the wild and no public exploit code.

## Other vulnerabilities in reactphp http

- [CVE-2022-36032](https://insights.sbomify.com/CVE-2022-36032/): ReactPHP's HTTP server parses encoded cookie names so malicious `__Host-` and `__Secure-` cookies can be sent (medium 5.3)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2023-26044 and fix it if it is affected.

What it is: CVE-2023-26044 is a medium-severity denial of service vulnerability in reactphp http, published on 17 May 2023. 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-2023-26044 in the wild and no public exploit code.

Affected packages and fixed versions:
- react/http (Packagist): affected from 0.8.0; fixed in 1.9.0
- react/http (Packagist): affected from 0.8.0; fixed in 1.9.0

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-2023-26044/ (Markdown: https://insights.sbomify.com/CVE-2023-26044/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2023-26044
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-26044
- OSV: https://osv.dev/vulnerability/CVE-2023-26044

---
From sbomify Insights: https://insights.sbomify.com/CVE-2023-26044/
Summaries are generated and may contain mistakes; the official description above is the record.