# CVE-2026-116269: MIME::Field::ParamVal versions before 5.521 for Perl turn an RFC 2231 filename with a hyphenated language tag into an empty recommended filename.


- **Severity:** Not scored
- **Exploited in the wild:** Not known
- **Fix available:** No
- **Published:** 28 Oct 2026
- **Updated:** 28 Oct 2026
- **Also known as:** DEBIAN-CVE-2026-116269, GHSA-h2xx-9xmf-ppmv, UBUNTU-CVE-2026-116269

## What is CVE-2026-116269?

CVE-2026-116269 is a vulnerability, published on 28 Oct 2026. 

### Official description

MIME::Field::ParamVal versions before 5.521 for Perl turn an RFC 2231 filename with a hyphenated language tag into an empty recommended filename.

A parameter such as filename*=utf-8'en-US'payload.exe is converted to an encoded word with the language tag appended to the charset. The decoder strips the language suffix only when it is a single word, so it cannot resolve the charset UTF-8*EN-US and returns an empty string. The recommended_filename() method returns that empty string rather than falling back to the name parameter.

Other mail readers return payload.exe. A remote sender can get an attachment past a policy that checks file extensions on the recommended filename.

Weakness: CWE-436 (Interpretation Conflict)

## Which versions are affected by CVE-2026-116269?


## How do I fix CVE-2026-116269?

No fix has been published for CVE-2026-116269 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-116269 being exploited?

There is no known exploitation of CVE-2026-116269 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-116269 and fix it if it is affected.

What it is: CVE-2026-116269 is a vulnerability, published on 28 Oct 2026. 
Exploitation: There is no known exploitation of CVE-2026-116269 in the wild and no public exploit code.

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-2026-116269/ (Markdown: https://insights.sbomify.com/CVE-2026-116269/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-116269
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-116269
- OSV: https://osv.dev/vulnerability/CVE-2026-116269

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From sbomify Insights: https://insights.sbomify.com/CVE-2026-116269/
Summaries are generated and may contain mistakes; the official description above is the record.