# CVE-2026-5037: mxml mxmlIndexNew mxml-index.c index_sort stack-based overflow

> A stack-based buffer overflow in mxml allows local attackers to execute arbitrary code or cause denial of service via crafted input.

- **Severity:** Medium 4.8 (`CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 29 Mar 2026
- **Updated:** 1 Apr 2026
- **Also known as:** DEBIAN-CVE-2026-5037, GHSA-2j9m-mc98-jvp7, OESA-2026-1860, UBUNTU-CVE-2026-5037

## What is CVE-2026-5037?

CVE-2026-5037 is a medium-severity memory corruption vulnerability in mxml, published on 29 Mar 2026. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

A vulnerability was determined in mxml up to 4.0.4. This issue affects the function index_sort of the file mxml-index.c of the component mxmlIndexNew. Executing a manipulation of the argument tempr can lead to stack-based buffer overflow. The attack is restricted to local execution. The exploit has been publicly disclosed and may be utilized. This patch is called 6e27354466092a1ac65601e01ce6708710bb9fa5. A patch should be applied to remediate this issue.

Weakness: CWE-121 (Stack-based Buffer Overflow), CWE-119 (Improper Restriction of Operations within the Bounds of a Memory Buffer)

## Which versions are affected by CVE-2026-5037?


## How do I fix CVE-2026-5037?

Apply the vendor's patch.

## Is CVE-2026-5037 being exploited?

There is no known exploitation of CVE-2026-5037 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-5037 and fix it if it is affected.

What it is: CVE-2026-5037 is a medium-severity memory corruption vulnerability in mxml, published on 29 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-2026-5037 in the wild and no public exploit code.

Affected product: mxml. 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-2026-5037/ (Markdown: https://insights.sbomify.com/CVE-2026-5037/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-5037
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-5037
- OSV: https://osv.dev/vulnerability/CVE-2026-5037

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-5037/
Summaries are generated and may contain mistakes; the official description above is the record.