# Authentication Bypass by Alternate Name in Apache Tomcat

Advisory record · `GHSA-36qh-35cm-5w2w`

- **Identifiers:** `GHSA-36qh-35cm-5w2w` · `BIT-tomcat-2021-30640` · `CVE-2021-30640`
- **State:** Confirmed
- **Severity:** CVSS 6.5 Medium
- **Critical:** No
- **Weakness (CWE):** [CWE-116](https://cwe.mitre.org/data/definitions/116.html) · [CWE-287](https://cwe.mitre.org/data/definitions/287.html) · [CWE-289](https://cwe.mitre.org/data/definitions/289.html)
- **Tags:** [Authentication bypass](https://agentprime.io/advisories/tag/auth-bypass.md) · [CWE-116](https://agentprime.io/advisories/tag/cwe-116.md) · [CWE-289](https://agentprime.io/advisories/tag/cwe-289.md)
- **Published:** 13 Aug 2021
- **Updated:** 19 Feb 2024
- **Reviewed by a person:** No

Published by the GitHub Advisory Database at 13 Aug 2021, 15:21 UTC. agentprime has not analysed this yet, so whether it affects any app is not known.

## Affected packages

- `org.apache.tomcat:tomcat` (Maven): affected `>=10.0.0-M1, <10.0.5 || >=9.0.0M1, <9.0.45 || >=8.5.0, <8.5.65`; fixed in `10.0.5`, `9.0.45`, `8.5.65`

## 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

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

- **CISA KEV:** Not listed.
- **EPSS:** 0.099, the 95th percentile, on 5 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.

## Timeline

This record came from the full history of the GitHub Advisory Database, published 13 Aug 2021. New records show when each source confirmed them.

## Sources

- [GitHub Advisory Database: GHSA-36qh-35cm-5w2w](https://github.com/advisories/GHSA-36qh-35cm-5w2w)
- [OSV: GHSA-36qh-35cm-5w2w](https://osv.dev/vulnerability/GHSA-36qh-35cm-5w2w)
- <https://nvd.nist.gov/vuln/detail/CVE-2021-30640>
- <https://lists.apache.org/thread.html/r59f9ef03929d32120f91f4ea7e6e79edd5688d75d0a9b65fd26d1fe8%40%3Cannounce.tomcat.apache.org%3E>
- <https://lists.debian.org/debian-lts-announce/2021/08/msg00009.html>
- <https://security.gentoo.org/glsa/202208-34>
- <https://security.netapp.com/advisory/ntap-20210827-0007>
- <https://www.debian.org/security/2021/dsa-4952>
- <https://www.debian.org/security/2021/dsa-4986>
- <https://www.oracle.com//security-alerts/cpujul2021.html>
- <https://www.oracle.com/security-alerts/cpujan2022.html>
- <https://www.oracle.com/security-alerts/cpuoct2021.html>

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-36qh-35cm-5w2w>, or `POST https://api.agentprime.io/v1/match` with your packages (<https://agentprime.io/api.md>)

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The web page: <https://agentprime.io/advisories/GHSA-36qh-35cm-5w2w/>. Everything for agents: <https://agentprime.io/llms.txt>.