cve/2018/CVE-2018-0732.md

### [CVE-2018-0732](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2018-0732)
![](https://img.shields.io/static/v1?label=Product&message=OpenSSL&color=blue)
![](https://img.shields.io/static/v1?label=Version&message=n%2Fa&color=blue)
![](https://img.shields.io/static/v1?label=Vulnerability&message=Client%20side%20Denial%20of%20Service&color=brighgreen)

### Description

During key agreement in a TLS handshake using a DH(E) based ciphersuite a malicious server can send a very large prime value to the client. This will cause the client to spend an unreasonably long period of time generating a key for this prime resulting in a hang until the client has finished. This could be exploited in a Denial Of Service attack. Fixed in OpenSSL 1.1.0i-dev (Affected 1.1.0-1.1.0h). Fixed in OpenSSL 1.0.2p-dev (Affected 1.0.2-1.0.2o).

### POC

#### Reference
- http://www.oracle.com/technetwork/security-advisory/cpuoct2018-4428296.html
- https://usn.ubuntu.com/3692-1/
- https://www.oracle.com/security-alerts/cpuapr2020.html
- https://www.oracle.com/security-alerts/cpujan2021.html
- https://www.oracle.com/technetwork/security-advisory/cpujan2019-5072801.html
- https://www.oracle.com/technetwork/security-advisory/cpuoct2019-5072832.html
- https://www.tenable.com/security/tns-2018-17

#### Github
- https://github.com/ARPSyndicate/cvemon
- https://github.com/RClueX/Hackerone-Reports
- https://github.com/chnzzh/OpenSSL-CVE-lib
- https://github.com/holmes-py/reports-summary
- https://github.com/imhunterand/hackerone-publicy-disclosed
- https://github.com/intrigueio/intrigue-ident
- https://github.com/javirodriguezzz/Shodan-Browser
- https://github.com/mrodden/vyger
- https://github.com/tlsresearch/TSI