cve/2023/CVE-2023-3776.md

### [CVE-2023-3776](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2023-3776)
![](https://img.shields.io/static/v1?label=Product&message=Kernel&color=blue)
![](https://img.shields.io/static/v1?label=Version&message=2.6%3C%206.5%20&color=brighgreen)
![](https://img.shields.io/static/v1?label=Vulnerability&message=CWE-416%20Use%20After%20Free&color=brighgreen)

### Description

A use-after-free vulnerability in the Linux kernel's net/sched: cls_fw component can be exploited to achieve local privilege escalation.If tcf_change_indev() fails, fw_set_parms() will immediately return an error after incrementing or decrementing the reference counter in tcf_bind_filter(). If an attacker can control the reference counter and set it to zero, they can cause the reference to be freed, leading to a use-after-free vulnerability.We recommend upgrading past commit 0323bce598eea038714f941ce2b22541c46d488f.

### POC

#### Reference
- http://packetstormsecurity.com/files/175072/Kernel-Live-Patch-Security-Notice-LSN-0098-1.html
- http://packetstormsecurity.com/files/175963/Kernel-Live-Patch-Security-Notice-LSN-0099-1.html

#### Github
- https://github.com/N1ghtu/RWCTF6th-RIPTC
- https://github.com/cvestone/CtfCollections