cve/2020/CVE-2020-13943.md

### [CVE-2020-13943](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2020-13943)
![](https://img.shields.io/static/v1?label=Product&message=Apache%20Tomcat&color=blue)
![](https://img.shields.io/static/v1?label=Version&message=n%2Fa&color=blue)
![](https://img.shields.io/static/v1?label=Vulnerability&message=Information%20Disclosure&color=brighgreen)

### Description

If an HTTP/2 client connecting to Apache Tomcat 10.0.0-M1 to 10.0.0-M7, 9.0.0.M1 to 9.0.37 or 8.5.0 to 8.5.57 exceeded the agreed maximum number of concurrent streams for a connection (in violation of the HTTP/2 protocol), it was possible that a subsequent request made on that connection could contain HTTP headers - including HTTP/2 pseudo headers - from a previous request rather than the intended headers. This could lead to users seeing responses for unexpected resources.

### POC

#### Reference
- https://www.oracle.com/security-alerts/cpuApr2021.html
- https://www.oracle.com/security-alerts/cpuApr2021.html

#### Github
- https://github.com/ARPSyndicate/cvemon
- https://github.com/Live-Hack-CVE/CVE-2020-13943
- https://github.com/vshaliii/Basic-Pentesting-2-Vulnhub-Walkthrough