cve/2019/CVE-2019-9517.md

### [CVE-2019-9517](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2019-9517)
![](https://img.shields.io/static/v1?label=Product&message=n%2Fa&color=blue)
![](https://img.shields.io/static/v1?label=Version&message=n%2Fa&color=blue)
![](https://img.shields.io/static/v1?label=Vulnerability&message=CWE-400%20Uncontrolled%20Resource%20Consumption&color=brighgreen)

### Description

Some HTTP/2 implementations are vulnerable to unconstrained interal data buffering, potentially leading to a denial of service. The attacker opens the HTTP/2 window so the peer can send without constraint; however, they leave the TCP window closed so the peer cannot actually write (many of) the bytes on the wire. The attacker then sends a stream of requests for a large response object. Depending on how the servers queue the responses, this can consume excess memory, CPU, or both.

### POC

#### Reference
- https://kb.cert.org/vuls/id/605641/
- https://www.oracle.com/security-alerts/cpuapr2020.html
- https://www.oracle.com/technetwork/security-advisory/cpuoct2019-5072832.html

#### Github
- https://github.com/florentvinai/CompteRendu-CTF-Mordor