{"schema":"threatline.record/2","record":{"id":"CVE-2021-3493","aliases":[],"summary":"Linux Kernel Privilege Escalation Vulnerability","details":"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.","categories":["Operating systems"],"product":"Kernel","vendor":"Linux","ecosystem":null,"affected_ranges":[{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2021-3493","source_modified_at":"2025-10-21T23:25:48.908Z","fetched_at":"2026-10-23T18:42:43.628194Z","product":"linux kernel","vendor":"Ubuntu","versions":[{"lessThan":"5.8.0-50.56","status":"affected","version":"5.8 kernel","versionType":"custom"},{"lessThan":"5.4.0-72.80","status":"affected","version":"5.4 kernel","versionType":"custom"},{"lessThan":"4.15.0-142.146","status":"affected","version":"4.15 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