cve/2021/CVE-2021-38209.md

### [CVE-2021-38209](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-38209)
![](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

net/netfilter/nf_conntrack_standalone.c in the Linux kernel before 5.12.2 allows observation of changes in any net namespace because these changes are leaked into all other net namespaces. This is related to the NF_SYSCTL_CT_MAX, NF_SYSCTL_CT_EXPECT_MAX, and NF_SYSCTL_CT_BUCKETS sysctls.

### POC

#### Reference
- https://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.12.2

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