# CVE-2021-22555: A Linux Kernel bug is being used in attacks

Status: Being used now (CISA KEV, added 2025-10-06)
Who: 
Do this: 

## Agent prompt (read-only)
Read-only check, change nothing, send nothing anywhere.
Is Linux Kernel (CVE-2021-22555) installed or running on this machine or in this project?
1. Find every copy and its version (apps, packages, containers, lockfiles).
2. Compare each version against the vendor's fixed version for CVE-2021-22555. Quote the vendor page you used.
3. Report a table: where, version, fixed version, status (exposed / fixed / not installed / unsure).
4. List the exact update steps, but do not run them.

## Official description
Linux Kernel contains a heap out-of-bounds write vulnerability that could allow an attacker to gain privileges or cause a DoS (via heap memory corruption) through user name space.

## Sources
- https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/net/netfilter/x_tables.c?id=9fa492cdc160cd27ce1046cb36f47d3b2b1efa21
- https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/net/netfilter/x_tables.c?id=b29c457a6511435960115c0f548c4360d5f4801d
- https://security.netapp.com/advisory/ntap-20210805-0010/
- https://github.com/google/security-research/security/advisories/GHSA-xxx5-8mvq-3528
- https://nvd.nist.gov/vuln/detail/CVE-2021-22555
- https://nvd.nist.gov/vuln/detail/CVE-2021-22555

Generated by isitexploited.org from public sources. Verify version numbers against the vendor before acting.