# CVE-2025-3986: Apereo CAS CasConfigurationMetadataServerController.java redos

> Remote attackers can cause denial of service in Apereo CAS via inefficient regular expression complexity in the configuration metadata server controller.

- **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:** No
- **Published:** 27 Apr 2025
- **Updated:** 28 Apr 2025
- **Also known as:** GHSA-mvwq-hcrj-f5x9

## What is CVE-2025-3986?

CVE-2025-3986 is a medium-severity denial of service vulnerability in Apereo CAS, published on 27 Apr 2025. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

A vulnerability was found in Apereo CAS 5.2.6. It has been declared as problematic. This vulnerability affects unknown code of the file cas-5.2.6\core\cas-server-core-configuration-metadata-repository\src\main\java\org\apereo\cas\metadata\rest\CasConfigurationMetadataServerController.java. The manipulation of the argument Name leads to inefficient regular expression complexity. The attack can be initiated remotely. The exploit has been disclosed to the public and may be used. The vendor was contacted early about this disclosure but did not respond in any way.

Weakness: CWE-400 (Uncontrolled Resource Consumption), CWE-1333 (Inefficient Regular Expression Complexity)

## Which versions are affected by CVE-2025-3986?

2 open source packages ship an affected version, including org.apereo.cas:cas-server-core-configuration-metadata-repository. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `org.apereo.cas:cas-server-core-configuration-metadata-repository` | Maven | All versions to 5.2.6 | None |
| `org.apereo.cas:cas-server-core-configuration-metadata-repository` | Maven | All versions to 5.2.6 | None |

Products: Apereo Central Authentication Service.

## How do I fix CVE-2025-3986?

No fix has been published for CVE-2025-3986 yet. Limit exposure of the affected software until one is available.

## Is CVE-2025-3986 being exploited?

There is no known exploitation of CVE-2025-3986 in the wild and no public exploit code.

## Other vulnerabilities in Apereo CAS

- [CVE-2023-4612](https://insights.sbomify.com/CVE-2023-4612/): MFA bypass in Apereo CAS (critical 9.8)
- [CVE-2024-4399](https://insights.sbomify.com/CVE-2024-4399/): CAS <= 1.0.0 - Unauthenticated SSRF (critical 9.1)
- [CVE-2019-10754](https://insights.sbomify.com/CVE-2019-10754/): Use of Insufficiently Random Values in Apereo CAS (high 8.1)
- [CVE-2020-27178](https://insights.sbomify.com/CVE-2020-27178/): Improper Authentication in Apereo CAS (high 7.5)
- [CVE-2015-1169](https://insights.sbomify.com/CVE-2015-1169/): Auth bypass in n/a (high 7.5)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2025-3986 and fix it if it is affected.

What it is: CVE-2025-3986 is a medium-severity denial of service vulnerability in Apereo CAS, published on 27 Apr 2025. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2025-3986 in the wild and no public exploit code.

Affected packages and fixed versions:
- org.apereo.cas:cas-server-core-configuration-metadata-repository (Maven): affected all versions up to 5.2.6; no fix listed
- org.apereo.cas:cas-server-core-configuration-metadata-repository (Maven): affected all versions up to 5.2.6; no fix listed

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-2025-3986/ (Markdown: https://insights.sbomify.com/CVE-2025-3986/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-3986
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-3986
- OSV: https://osv.dev/vulnerability/CVE-2025-3986

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-3986/
Summaries are generated and may contain mistakes; the official description above is the record.