CVE-2021-3493VulnerabilityPublished 10/20/2022Updated 10/24/2026
CVE-2021-3493: Linux Kernel Privilege Escalation Vulnerability
Affects Linux KernelSource CISA KEV
Severity
HighNo CVSS score published yet
- Exploitation
Actively exploited – in CISA KEV since 10/20/2022
- KEV deadline
- 11/10/2022
- EPSS
- 49.2% chance of exploitation in 30 days – higher than 98% of CVEs
What to do
CISA required action
Apply updates per vendor instructions.
Description
The overlayfs stacking file system in Linux kernel does not properly validate the application of file capabilities against user namespaces, which could lead to privilege escalation.