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CVE-2021-3493: Linux Kernel Privilege Escalation Vulnerability
Linux Kernel · in CISA KEV since 2022-10-20
2022-10-20added to KEV
2022-11-10federal remediation due date
49.17%EPSS exploit probability (30 days) 98.8th percentile
7.8 HIGHCVSS 3.1
Unknownknown ransomware use
551days from NVD publication to KEV
What it is
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 (CISA)
Apply updates per vendor instructions.
| CWE | CWE-862 |
|---|---|
| CVSS vector | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
| NVD published | 2021-04-17 (Analyzed) |
Original records: NVD · CISA KEV · JSON: /api/cve/CVE-2021-3493.json · all KEV CVEs
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Get the full file: Exploited Vulnerabilities Brief – September 2026 ($29): this month's KEV additions ranked by EPSS, ransomware use and due date, ready to hand to a patch team. Checkout by Polar.