CVE-2021-3493
Linux Kernel Privilege Escalation Vulnerability
Summary
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 software
Vendor: Linux · Product: Kernel
Weakness types (CWE):
What to do
This vulnerability appears in CISA's Known Exploited Vulnerabilities catalog, meaning it is being exploited in the wild. Prioritize patching affected systems and verify exposure across your estate.
Related vulnerabilities in Linux
| CVE | Name | EPSS | Exploited |
|---|---|---|---|
| CVE-2026-31431 | Linux Kernel Incorrect Resource Transfer Between Spheres Vulnerability | 94.5% | Yes |
| CVE-2022-0847 | Linux Kernel Privilege Escalation Vulnerability | 88.6% | Yes |
| CVE-2016-5195 | Linux Kernel Race Condition Vulnerability | 83.0% | Yes |
| CVE-2021-22555 | Linux Kernel Heap Out-of-Bounds Write Vulnerability | 78.7% | Yes |
| CVE-2019-13272 | Linux Kernel Improper Privilege Management Vulnerability | 52.2% | Yes |
| CVE-2013-2094 | Linux Kernel Privilege Escalation Vulnerability | 47.7% | Yes |
| CVE-2013-6282 | Linux Kernel Improper Input Validation Vulnerability | 39.7% | Yes |
| CVE-2014-3153 | Linux Kernel Privilege Escalation Vulnerability | 37.2% | Yes |
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