# CVE-2026-3234: Mod_proxy_cluster: mod_proxy_cluster: response body corruption via crlf injection

> Remote attackers can corrupt INFO endpoint responses via CRLF injection in mod_proxy_cluster without authentication, affecting Red Hat JBoss Core Services.

- **Severity:** Medium 4.3 (`CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 12 Mar 2026
- **Updated:** 12 Mar 2026
- **Also known as:** GHSA-rxq8-r4ww-hxv7

## What is CVE-2026-3234?

CVE-2026-3234 is a medium-severity vulnerability in Red Hat Enterprise Linux 10, published on 12 Mar 2026. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

A flaw was found in  mod_proxy_cluster. This vulnerability, a Carriage Return Line Feed (CRLF) injection in the decodeenc() function, allows a remote attacker to bypass input validation. By injecting CRLF sequences into the cluster configuration, an attacker can corrupt the response body of INFO endpoint responses. Exploitation requires network access to the MCMP protocol port, but no authentication is needed.

Weakness: CWE-93 (Improper Neutralization of CRLF Sequences)

## Which versions are affected by CVE-2026-3234?


## How do I fix CVE-2026-3234?

No fix has been published for CVE-2026-3234 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-3234 being exploited?

There is no known exploitation of CVE-2026-3234 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-3234 and fix it if it is affected.

What it is: CVE-2026-3234 is a medium-severity vulnerability in Red Hat Enterprise Linux 10, published on 12 Mar 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-3234 in the wild and no public exploit code.

Affected product: Red Hat Enterprise Linux 10. No package-level version data is available, so check the vendor advisory linked from the reference page.

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-2026-3234/ (Markdown: https://insights.sbomify.com/CVE-2026-3234/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-3234
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-3234
- OSV: https://osv.dev/vulnerability/CVE-2026-3234

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-3234/
Summaries are generated and may contain mistakes; the official description above is the record.