CVE Watch—

CVE-2021-3493

Linux Kernel Privilege Escalation Vulnerability

CVSS

—

No CVSS

EPSS

49.2%

p99

KEV

YES

Oct 20, 2022

Exploit Today

0-100

Published: — · Last modified: —

EPSS · 30d

49.2%EPSS · 30 days49.2%

2026-09-172026-10-15

KEV catalog record

Product

Linux / Kernel

Vulnerability

Linux Kernel Privilege Escalation Vulnerability

Added to KEV

Oct 20, 2022

Remediate by

Nov 10, 2022

Known ransomware use

Summary 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.

Required action

Apply updates per vendor instructions.

Notes

https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=7c03e2cda4a584cadc398e8f6641ca9988a39d52; https://nvd.nist.gov/vuln/detail/CVE-2021-3493

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