# CVE-2026-77121: Nexus Repository 3 - Denial of Service via Unbounded Maven POM Metadata Fields

> Authenticated users can cause permanent denial of service in a specific Maven repository by uploading oversized POM metadata, requiring admin intervention to fix.

- **Severity:** Medium 5.3 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 2 Sep 2026
- **Updated:** 2 Sep 2026
- **Also known as:** GHSA-747h-p664-p8p7, MINI-jf22-xf7m-xpm5, MINI-p5h4-7xjg-3qr2

## What is CVE-2026-77121?

CVE-2026-77121 is a medium-severity denial of service vulnerability in Sonatype Nexus Repository Manager, published on 2 Sep 2026. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

A user account with permission to deploy artifacts to a hosted Maven repository could upload a POM file containing an oversized metadata field. This causes future attempts to list or browse that repository's components to permanently fail until an administrator repairs the underlying data. Only the targeted repository is affected; other repositories and overall server health remain unaffected.

Weakness: CWE-770 (Allocation of Resources Without Limits or Throttling)

## Which versions are affected by CVE-2026-77121?

It affects 1 product.


Products: Sonatype Nexus Repository Manager.

## How do I fix CVE-2026-77121?

Apply the vendor's patch.

## Is CVE-2026-77121 being exploited?

There is no known exploitation of CVE-2026-77121 in the wild and no public exploit code.

## Other vulnerabilities in Sonatype Nexus Repository Manager

- [CVE-2019-7238](https://insights.sbomify.com/CVE-2019-7238/): Sonatype Nexus Repository Manager Incorrect Access Control (critical 9.8, exploited in the wild)
- [CVE-2019-9629](https://insights.sbomify.com/CVE-2019-9629/): Hardcoded credentials in n/a (critical 9.8)
- [CVE-2017-17717](https://insights.sbomify.com/CVE-2017-17717/): Hardcoded credentials in n/a (critical 9.8)
- [CVE-2026-3199](https://insights.sbomify.com/CVE-2026-3199/): Nexus Repository 3 - Authenticated Remote Code Execution via Task Property Injection (critical 9.4)
- [CVE-2026-5189](https://insights.sbomify.com/CVE-2026-5189/): Nexus Repository 3 - Hardcoded Credential in Internal Database Component (critical 9.2)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-77121 and fix it if it is affected.

What it is: CVE-2026-77121 is a medium-severity denial of service vulnerability in Sonatype Nexus Repository Manager, published on 2 Sep 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-77121 in the wild and no public exploit code.

Affected product: Sonatype Nexus Repository Manager. 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-2026-77121/ (Markdown: https://insights.sbomify.com/CVE-2026-77121/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-77121
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-77121
- OSV: https://osv.dev/vulnerability/CVE-2026-77121

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-77121/
Summaries are generated and may contain mistakes; the official description above is the record.