# CVE-2026-115721: Apache Vysper: Unbounded allocation


- **Severity:** High 7.5 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Fix available:** No
- **Published:** 26 Oct 2026
- **Updated:** 26 Oct 2026
- **Also known as:** GHSA-8jc8-88rj-r6ww

## What is CVE-2026-115721?

CVE-2026-115721 is a high-severity vulnerability in Apache Vysper, published on 26 Oct 2026. 

### Official description

**UNSUPPORTED WHEN ASSIGNED**  Unbounded allocation in XML parsing in Apache Vysper; all versions, may lead to an out of memory condition.

This issue affects all versions of Apache Vysper. Apache Vysper is an XMPP (Jabber) server library.

As this project is retired, we do not plan to release a version that fixes this issue. Users are recommended to find an alternative.

## Which versions are affected by CVE-2026-115721?


## How do I fix CVE-2026-115721?

No fix has been published for CVE-2026-115721 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-115721 being exploited?

There is no known exploitation of CVE-2026-115721 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-115721 and fix it if it is affected.

What it is: CVE-2026-115721 is a high-severity vulnerability in Apache Vysper, published on 26 Oct 2026. 
Exploitation: There is no known exploitation of CVE-2026-115721 in the wild and no public exploit code.

Affected product: Apache Vysper. 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-2026-115721/ (Markdown: https://insights.sbomify.com/CVE-2026-115721/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-115721
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-115721
- OSV: https://osv.dev/vulnerability/CVE-2026-115721

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-115721/
Summaries are generated and may contain mistakes; the official description above is the record.