# HTTP Request Smuggling in Apache Tomcat

Advisory record · `GHSA-4vww-mc66-62m6`

- **Identifiers:** `GHSA-4vww-mc66-62m6` · `BIT-tomcat-2021-33037` · `CVE-2021-33037`
- **State:** Confirmed
- **Severity:** CVSS 5.3 Medium
- **Critical:** No
- **Weakness (CWE):** [CWE-444](https://cwe.mitre.org/data/definitions/444.html)
- **Tags:** [HTTP request smuggling](https://agentprime.io/advisories/tag/request-smuggling.md)
- **Published:** 13 Aug 2021
- **Updated:** 11 Mar 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, <10.0.7 || >=9.0.0-M1, <9.0.48 || >=8.5.0, <8.5.68`; fixed in `10.0.7`, `9.0.48`, `8.5.68`

## 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

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

- **CISA KEV:** Not listed.
- **EPSS:** 0.75, the 99th percentile, on 7 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.

## Timeline

- 31 Oct 2026, 15:13 UTC: First seen by agentprime
- 31 Oct 2026, 15:13 UTC: [Confirmed by OSV](https://osv.dev/vulnerability/GHSA-4vww-mc66-62m6)

## Sources

- [GitHub Advisory Database: GHSA-4vww-mc66-62m6](https://github.com/advisories/GHSA-4vww-mc66-62m6)
- [OSV: GHSA-4vww-mc66-62m6](https://osv.dev/vulnerability/GHSA-4vww-mc66-62m6)
- <https://nvd.nist.gov/vuln/detail/CVE-2021-33037>
- <https://github.com/apache/tomcat/commit/05f9e8b00f5d9251fcd3c95dcfd6cf84177f46c8>
- <https://github.com/apache/tomcat/commit/19d11556d0db99df291df33605f137976d152475>
- <https://github.com/apache/tomcat/commit/3202703e6d635e39b74262e81f0cb4bcbe2170dc>
- <https://github.com/apache/tomcat/commit/45d70a86a901cbd534f8f570bed2aec9f7f7b88e>
- <https://github.com/apache/tomcat/commit/506134f957a4be2c5b4a9334f7b3435fc954dbc1>
- <https://github.com/apache/tomcat/commit/8874fa02e9b36baa9ca6b226c0882c0190ca5a02>
- <https://github.com/apache/tomcat/commit/a2c3dc4c96168743ac0bab613709a5bbdaec41d0>
- <https://github.com/apache/tomcat/commit/da0e7cb093cf68b052d9175e469dbd0464441b0b>
- <https://github.com/apache/tomcat/commit/eee0d024c1b3171560c92eaba79dd6eb8eb11bcd>
- <https://security.gentoo.org/glsa/202208-34>
- <https://security.netapp.com/advisory/ntap-20210827-0007>

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-4vww-mc66-62m6>, 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-4vww-mc66-62m6/>. Everything for agents: <https://agentprime.io/llms.txt>.