# Origin Validation Error in Apache Maven

Advisory record · `GHSA-2f88-5hg8-9x2x`

- **Identifiers:** `GHSA-2f88-5hg8-9x2x` · `BIT-maven-2021-26291` · `CVE-2021-26291`
- **State:** Confirmed
- **Severity:** CVSS 9.1 Critical
- **Critical:** Yes: CVSS 9+
- **Weakness (CWE):** [CWE-346](https://cwe.mitre.org/data/definitions/346.html)
- **Tags:** [CWE-346](https://agentprime.io/advisories/tag/cwe-346.md)
- **Published:** 16 Jun 2021
- **Updated:** 10 Sept 2026
- **Reviewed by a person:** No

Published by the GitHub Advisory Database at 16 Jun 2021, 17:32 UTC. agentprime has not analysed this yet, so whether it affects any app is not known.

## Critical

Critical, because:

- CVSS score 9.1: 9.0 or more.

How we decide what’s critical: <https://agentprime.io/advisories/critical.md>

## Affected packages

- `org.apache.maven:maven-compat` (Maven): affected `<3.8.1`; fixed in `3.8.1`
- `org.apache.maven:maven-core` (Maven): affected `<3.8.1`; fixed in `3.8.1`

## Machine-written summary

Summary written by Claude Haiku from the source advisory. Not reviewed by a person.

> Maven's maven-compat and maven-core packages before 3.8.1 follow repositories defined in a dependency's pom, including plain http ones. An attacker who controls such a repository, or can impersonate it on the network, could supply malicious dependencies to the build. Upgrade to 3.8.1 or later, which no longer follows http repository references by default.

Written 2 Nov 2026.

## Not analysed yet

We haven’t published our analysis of this Advisory yet. Once a person has reviewed it, this page will say what’s vulnerable, what has to be true for your app to be affected, and how to check.

## Severity and exploitation

- 9.1 Critical, CVSS 3.1: `CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N`, from GitHub Advisory Database

- **CISA KEV:** Not listed.
- **EPSS:** 0.087, the 95th percentile, on 12 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.

## Timeline

- 31 Oct 2026, 14:18 UTC: First seen by agentprime
- 31 Oct 2026, 14:18 UTC: [Confirmed by OSV](https://osv.dev/vulnerability/GHSA-2f88-5hg8-9x2x)

## Sources

- [GitHub Advisory Database: GHSA-2f88-5hg8-9x2x](https://github.com/advisories/GHSA-2f88-5hg8-9x2x)
- [OSV: GHSA-2f88-5hg8-9x2x](https://osv.dev/vulnerability/GHSA-2f88-5hg8-9x2x)
- <https://nvd.nist.gov/vuln/detail/CVE-2021-26291>
- <https://github.com/apache/maven/commit/899465aeec03753ea91e15a79579eab76369c016>
- <https://github.com/apache/maven/commit/fa79cb22e456cc65522b5bab8c4240fe08c5775f>
- <https://lists.apache.org/thread.html/r77af3ac7c3bfbd5454546e13faf7aec21d627bdcf36c9ca240436b94@%3Cissues.karaf.apache.org%3E>
- <https://lists.apache.org/thread.html/r78fb6d2cf0ca332cfa43abd4471e75fa6c517ed9cdfcb950bff48d40@%3Cjira.kafka.apache.org%3E>
- <https://lists.apache.org/thread.html/r86aebd0387ae19b740b3eb28bad83fe6aceca0d6257eaa810a6e0002@%3Ccommits.kafka.apache.org%3E>
- <https://lists.apache.org/thread.html/r86e1c81e03f441855f127980e9b3d41939d04a7caea2b7ab718e2288@%3Cjira.kafka.apache.org%3E>
- <https://lists.apache.org/thread.html/r96cc126d3ee9aa42af9d3bb4baa94828b0a5f656584a50dcc594125f@%3Cissues.karaf.apache.org%3E>
- <https://lists.apache.org/thread.html/r9a027668558264c4897633e66bcb7784099fdec9f9b22c38c2442f00%40%3Cusers.maven.apache.org%3E>
- <https://lists.apache.org/thread.html/r9a027668558264c4897633e66bcb7784099fdec9f9b22c38c2442f00@%3Cusers.maven.apache.org%3E>
- <https://lists.apache.org/thread.html/ra88a0eba7f84658cefcecc0143fd8bbad52c229ee5dfcbfdde7b6457@%3Cdev.jena.apache.org%3E>
- <https://lists.apache.org/thread.html/ra9d984eccfd2ae7726671e025f0296bf03786e5cdf872138110ac29b@%3Ccommits.druid.apache.org%3E>

Facts on this page come from the GitHub Advisory Database (CC-BY 4.0), OSV and the other sources listed, as published. We don’t reproduce full advisory descriptions, which can contain exploit code.

## Check whether this affects you

A Match means an installed version is in the affected range above. Most don’t affect the app; agentprime hasn’t analysed this one yet.

- With the agentprime MCP server (<https://api.agentprime.io/mcp>), ask your agent to check the project: `check_lockfile` sends a lockfile, `check_packages` a list of installed packages, and both return the Matches and the upgrades that clear them. `get_advisory` returns this record. Setup: <https://agentprime.io/mcp.md>
- In a browser: <https://agentprime.io/check/> reads your lockfile in the browser, never uploading it.
- Whether it touches your code, with file and line: the Claude Code plugin, <https://agentprime.io/plugin.md>
- As JSON: <https://api.agentprime.io/v1/advisories/GHSA-2f88-5hg8-9x2x>, or `POST https://api.agentprime.io/v1/match` with your packages (<https://agentprime.io/api.md>)

---

The web page: <https://agentprime.io/advisories/GHSA-2f88-5hg8-9x2x/>. Everything for agents: <https://agentprime.io/llms.txt>.