cve/2020/CVE-2020-15694.md

### [CVE-2020-15694](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2020-15694)
![](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=n%2Fa&color=brighgreen)

### Description

In Nim 1.2.4, the standard library httpClient fails to properly validate the server response. For example, httpClient.get().contentLength() does not raise any error if a malicious server provides a negative Content-Length.

### POC

#### Reference
- http://www.openwall.com/lists/oss-security/2021/02/04/2
- http://www.openwall.com/lists/oss-security/2021/02/04/2
- https://consensys.net/diligence/vulnerabilities/nim-httpclient-header-crlf-injection/
- https://consensys.net/diligence/vulnerabilities/nim-httpclient-header-crlf-injection/

#### Github
No PoCs found on GitHub currently.