CVE Database · CVE-2021-3493
CVSS v3.1
8.8
EPSS
43.99%
Published
Apr 17, 2021
Modified
Oct 28, 2025
CISA Known Exploited Vulnerability
Added: 2022-10-20 · Due: 2022-11-10
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Public PoC / Exploit (9)
All weaponized →Links to public security research (Exploit-DB, Nuclei, Trickest, GitHub) for defensive use only.
Description
The overlayfs implementation in the linux kernel did not properly validate with respect to user namespaces the setting of file capabilities on files in an underlying file system. Due to the combination of unprivileged user namespaces along with a patch carried in the Ubuntu kernel to allow unprivileged overlay mounts, an attacker could use this to gain elevated privileges.
CVSS Vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:HWeaknesses (CWE)
Affected Products (3)
References (13)