cve/2019/CVE-2019-11479.md

### [CVE-2019-11479](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2019-11479)
![](https://img.shields.io/static/v1?label=Product&message=Linux%20kernel&color=blue)
![](https://img.shields.io/static/v1?label=Version&message=4.4%3C%204.4.182%20&color=brighgreen)
![](https://img.shields.io/static/v1?label=Vulnerability&message=CWE-405%20Asymmetric%20Resource%20Consumption%20(Amplification)&color=brighgreen)

### Description

Jonathan Looney discovered that the Linux kernel default MSS is hard-coded to 48 bytes. This allows a remote peer to fragment TCP resend queues significantly more than if a larger MSS were enforced. A remote attacker could use this to cause a denial of service. This has been fixed in stable kernel releases 4.4.182, 4.9.182, 4.14.127, 4.19.52, 5.1.11, and is fixed in commits 967c05aee439e6e5d7d805e195b3a20ef5c433d6 and 5f3e2bf008c2221478101ee72f5cb4654b9fc363.

### POC

#### Reference
- https://kb.pulsesecure.net/articles/Pulse_Security_Advisories/SA44193
- https://www.oracle.com/security-alerts/cpujan2020.html
- https://www.oracle.com/security-alerts/cpuoct2020.html

#### Github
- https://github.com/DevOps-spb-org/Linux-docs
- https://github.com/Ivan-778/docLinux
- https://github.com/hightemp/docLinux
- https://github.com/kaosagnt/ansible-everyday
- https://github.com/misanthropos/FFFFM