CVE-2021-3493
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.
ACTIVELY EXPLOITED IN THE WILD
This vulnerability is listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.
Linux Kernel Privilege Escalation Vulnerability
Linux Kernel
Apply updates per vendor instructions.
10/20/2022
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=7c03e2cda4a584cadc398e8f6641ca9988a39d52; https://nvd.nist.gov/vuln/detail/CVE-2021-3493
Vulnerability Summary
CVSS v3 Score
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
CVSS v2 Score
AV:L/AC:L/Au:N/C:C/I:C/A:C
EPSS Score (Exploitation Probability)
This vulnerability has a 79.71% probability of being exploited in the next 30 days, ranking higher than 99% of all scored CVEs.
CWE Classification
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Similar SeverityHIGH
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