CVE-2021-3493
Published: Apr 17, 2021
Modified: Oct 21, 2025
CVSS v3.1
8.8
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.
| Vendor | Product | Versions |
|---|---|---|
Ubuntu | linux kernel | affected 5.8 kernel - < 5.8.0-50.56affected 5.4 kernel - < 5.4.0-72.80affected 4.15 kernel - < 4.15.0-142.146affected 4.4 kernel - < 4.4.0-209.241 |
Weaknesses (CWE)
CVSS v3.1 Details
CVSS v3.1 Vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
Attack Vector
Attack Complexity
Privileges Required
User Interaction
Scope
Confidentiality
Integrity
Availability
References
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