{"schema":"threatline.record/2","record":{"id":"CVE-2021-22555","aliases":["GHSA-xxx5-8mvq-3528"],"summary":"Linux Kernel Heap Out-of-Bounds Write Vulnerability","details":"Linux Kernel contains a heap out-of-bounds write vulnerability that could allow an attacker to gain privileges or cause a DoS (via heap memory corruption) through user name space.","categories":["Operating systems"],"product":"Kernel","vendor":"Linux","ecosystem":null,"affected_ranges":[{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2021-22555","source_modified_at":"2025-12-30T20:32:33.647Z","fetched_at":"2026-10-23T18:42:43.628194Z","product":"Linux Kernel","vendor":"n/a","versions":[{"lessThan":"unspecified","status":"affected","version":"2.6.19-rc1","versionType":"custom"}],"defaultStatus":null},{"source":"GitHub Advisory 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unavailable.","ransomware_campaign_use":"Unknown"},"epss":{"probability":0.78684,"percentile":0.9959,"score_date":"2026-10-23"},"published_at":"2021-07-07T11:20:10.668Z","modified_at":"2025-12-30T20:32:33.647Z","provenance":[{"source":"CISA KEV","url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","fetched_at":"2026-10-23T18:42:43.628194Z","source_modified_at":"2026-10-23T17:00:09.9001Z"},{"source":"CVE List","url":"https://www.cve.org/CVERecord?id=CVE-2021-22555","fetched_at":"2026-10-23T18:42:43.628194Z","source_modified_at":"2025-12-30T20:32:33.647Z"},{"source":"GitHub Advisory 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List","url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-22555","tags":["government-resource"]}],"locations":[],"motoko_assessment":{"status":"requires_architecture_review","automatic_remediation":false},"cve_state":"PUBLISHED","cvss_source":"CVE List","ssvc":{"exploitation":"active","automatable":"no","technical_impact":"total","assessed_at":"2025-10-04T03:55:24.534831Z"},"exploits":[{"added":"2025-02-28","check":true,"date":"2021-07-07","kind":"Exploit module","name":"Netfilter x_tables Heap OOB Write Privilege Escalation","source":"Metasploit","url":"https://github.com/rapid7/metasploit-framework/blob/master/modules/exploits/linux/local/netfilter_xtables_heap_oob_write_priv_esc.rb"},{"added":"2021-07-16","date":"2021-07-15","kind":"Local exploit","name":"Linux Kernel 2.6.19 < 5.9 - 'Netfilter Local Privilege 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