CVE-2021-3493
CISA KEVPublished October 20, 2022 · Updated April 3, 2026
high
Official 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.
Affected Products
| Vendor | Product |
|---|---|
| Linux | Kernel |
Patch Status
Patch by 2022-11-10
Recommended Actions
- Check if your systems use any of the affected products listed above.
- Apply vendor patches immediately if available.
- This vulnerability is in CISA's Known Exploited Vulnerabilities catalog — prioritize remediation.
- Monitor vendor advisories for updates and additional mitigations.
- Review logs for indicators of compromise related to CVE-2021-3493.