# CVE-2021-33037: tomcat9-docs: Apache Tomcat 10.0.0-M1 to 10.0.6, 9.0.0.M1 to 9.0.46 and 8.5.0 to 8.5.66 did not correctly parse the HTTP transfer-e...

CVE-2021-33037 is fixed in 15 products on 1 platform, first by libtomcat9-embed-java 9.0.16-3ubuntu0.18.04.2, released September 16, 2021. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2021-33037
- Priority: Routine
- CVSS: n/a (Medium)
- EPSS: 0.7467
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Jul 12, 2021

## Description

Apache Tomcat 10.0.0-M1 to 10.0.6, 9.0.0.M1 to 9.0.46 and 8.5.0 to 8.5.66 did not correctly parse the HTTP transfer-encoding request header in some circumstances leading to the possibility to request smuggling when used with a reverse proxy. Specifically: - Tomcat incorrectly ignored the transfer encoding header if the client declared it would only accept an HTTP/1.0 response; - Tomcat honoured the identify encoding; and - Tomcat did not ensure that, if present, the chunked encoding was the final encoding.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | libtomcat9-embed-java Ubuntu 18.04.6 LTS (bionic) | 9.0.16-3ubuntu0.18.04.2 | [libtomcat9-embed-java 9.0.16-3ubuntu0.18.04.2](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-libtomcat9-embed-java-9.0.16-3ubuntu0.18.04.2.md) | Sep 16, 2021 |
| Linux | libtomcat9-embed-java Ubuntu 20.04 LTS (focal) | 9.0.31-1ubuntu0.2 | [libtomcat9-embed-java 9.0.31-1ubuntu0.2](https://patchblox.com/security/data/fix/linux/ubuntu-focal-libtomcat9-embed-java-9.0.31-1ubuntu0.2.md) | Sep 16, 2021 |
| Linux | libtomcat9-java Ubuntu 18.04.6 LTS (bionic) | 9.0.16-3ubuntu0.18.04.2 | [libtomcat9-java 9.0.16-3ubuntu0.18.04.2](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-libtomcat9-java-9.0.16-3ubuntu0.18.04.2.md) | Sep 16, 2021 |
| Linux | libtomcat9-java Ubuntu 20.04 LTS (focal) | 9.0.31-1ubuntu0.2 | [libtomcat9-java 9.0.31-1ubuntu0.2](https://patchblox.com/security/data/fix/linux/ubuntu-focal-libtomcat9-java-9.0.31-1ubuntu0.2.md) | Sep 16, 2021 |
| Linux | tomcat9 Ubuntu 18.04.6 LTS (bionic) | 9.0.16-3ubuntu0.18.04.2 | [tomcat9 9.0.16-3ubuntu0.18.04.2](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-tomcat9-9.0.16-3ubuntu0.18.04.2.md) | Sep 16, 2021 |
| Linux | tomcat9 Ubuntu 20.04 LTS (focal) | 9.0.31-1ubuntu0.2 | [tomcat9 9.0.31-1ubuntu0.2](https://patchblox.com/security/data/fix/linux/ubuntu-focal-tomcat9-9.0.31-1ubuntu0.2.md) | Sep 16, 2021 |
| Linux | tomcat9 amzn 2023 | 1:9.0.64-1.amzn2023.0.2 | [ALAS2023-2023-059](https://patchblox.com/security/data/fix/linux/alas2023-2023-059.md) | Feb 17, 2023 |
| Linux | tomcat9-admin Ubuntu 18.04.6 LTS (bionic) | 9.0.16-3ubuntu0.18.04.2 | [tomcat9-admin 9.0.16-3ubuntu0.18.04.2](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-tomcat9-admin-9.0.16-3ubuntu0.18.04.2.md) | Sep 16, 2021 |
| Linux | tomcat9-admin Ubuntu 20.04 LTS (focal) | 9.0.31-1ubuntu0.2 | [tomcat9-admin 9.0.31-1ubuntu0.2](https://patchblox.com/security/data/fix/linux/ubuntu-focal-tomcat9-admin-9.0.31-1ubuntu0.2.md) | Sep 16, 2021 |
| Linux | tomcat9-admin-webapps amzn 2023 | 1:9.0.64-1.amzn2023.0.2 | [ALAS2023-2023-059](https://patchblox.com/security/data/fix/linux/alas2023-2023-059.md) | Feb 17, 2023 |
| Linux | tomcat9-common Ubuntu 18.04.6 LTS (bionic) | 9.0.16-3ubuntu0.18.04.2 | [tomcat9-common 9.0.16-3ubuntu0.18.04.2](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-tomcat9-common-9.0.16-3ubuntu0.18.04.2.md) | Sep 16, 2021 |
| Linux | tomcat9-common Ubuntu 20.04 LTS (focal) | 9.0.31-1ubuntu0.2 | [tomcat9-common 9.0.31-1ubuntu0.2](https://patchblox.com/security/data/fix/linux/ubuntu-focal-tomcat9-common-9.0.31-1ubuntu0.2.md) | Sep 16, 2021 |
| Linux | tomcat9-docs Ubuntu 18.04.6 LTS (bionic) | 9.0.16-3ubuntu0.18.04.2 | [tomcat9-docs 9.0.16-3ubuntu0.18.04.2](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-tomcat9-docs-9.0.16-3ubuntu0.18.04.2.md) | Sep 16, 2021 |
| Linux | tomcat9-docs Ubuntu 20.04 LTS (focal) | 9.0.31-1ubuntu0.2 | [tomcat9-docs 9.0.31-1ubuntu0.2](https://patchblox.com/security/data/fix/linux/ubuntu-focal-tomcat9-docs-9.0.31-1ubuntu0.2.md) | Sep 16, 2021 |
| Linux | tomcat9-docs-webapp amzn 2023 | 1:9.0.64-1.amzn2023.0.2 | [ALAS2023-2023-059](https://patchblox.com/security/data/fix/linux/alas2023-2023-059.md) | Feb 17, 2023 |
| Linux | tomcat9-el-3.0-api amzn 2023 | 1:9.0.64-1.amzn2023.0.2 | [ALAS2023-2023-059](https://patchblox.com/security/data/fix/linux/alas2023-2023-059.md) | Feb 17, 2023 |
| Linux | tomcat9-examples Ubuntu 18.04.6 LTS (bionic) | 9.0.16-3ubuntu0.18.04.2 | [tomcat9-examples 9.0.16-3ubuntu0.18.04.2](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-tomcat9-examples-9.0.16-3ubuntu0.18.04.2.md) | Sep 16, 2021 |
| Linux | tomcat9-examples Ubuntu 20.04 LTS (focal) | 9.0.31-1ubuntu0.2 | [tomcat9-examples 9.0.31-1ubuntu0.2](https://patchblox.com/security/data/fix/linux/ubuntu-focal-tomcat9-examples-9.0.31-1ubuntu0.2.md) | Sep 16, 2021 |
| Linux | tomcat9-jsp-2.3-api amzn 2023 | 1:9.0.64-1.amzn2023.0.2 | [ALAS2023-2023-059](https://patchblox.com/security/data/fix/linux/alas2023-2023-059.md) | Feb 17, 2023 |
| Linux | tomcat9-lib amzn 2023 | 1:9.0.64-1.amzn2023.0.2 | [ALAS2023-2023-059](https://patchblox.com/security/data/fix/linux/alas2023-2023-059.md) | Feb 17, 2023 |
| Linux | tomcat9-servlet-4.0-api amzn 2023 | 1:9.0.64-1.amzn2023.0.2 | [ALAS2023-2023-059](https://patchblox.com/security/data/fix/linux/alas2023-2023-059.md) | Feb 17, 2023 |
| Linux | tomcat9-user Ubuntu 18.04.6 LTS (bionic) | 9.0.16-3ubuntu0.18.04.2 | [tomcat9-user 9.0.16-3ubuntu0.18.04.2](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-tomcat9-user-9.0.16-3ubuntu0.18.04.2.md) | Sep 16, 2021 |
| Linux | tomcat9-user Ubuntu 20.04 LTS (focal) | 9.0.31-1ubuntu0.2 | [tomcat9-user 9.0.31-1ubuntu0.2](https://patchblox.com/security/data/fix/linux/ubuntu-focal-tomcat9-user-9.0.31-1ubuntu0.2.md) | Sep 16, 2021 |
| Linux | tomcat9-webapps amzn 2023 | 1:9.0.64-1.amzn2023.0.2 | [ALAS2023-2023-059](https://patchblox.com/security/data/fix/linux/alas2023-2023-059.md) | Feb 17, 2023 |

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