{"id":"CVE-2021-1048","published":"2021-12-15T19:15:14Z","modified":"2026-06-17T03:30:51Z","title":"Android Kernel Use-After-Free Vulnerability","vendor":"Android","product":"Kernel","tier":"core","eol":null,"description":{"text":"In ep_loop_check_proc of eventpoll.c, there is a possible way to corrupt memory due to a use after free. This could lead to local escalation of privilege with no additional execution privileges needed. User interaction is not needed for exploitation.Product: AndroidVersions: Android kernelAndroid ID: A-204573007References: Upstream kernel","provenance":"source","from":"NVD"},"summary":{"text":"A use-after-free flaw in the ep_loop_check_proc function of eventpoll.c in the Android kernel can corrupt memory. An attacker with local access and low privileges, requiring no user interaction, can exploit it to escalate privileges.","provenance":"ai","model":"claude-haiku-5-5","generatedAt":"2026-10-23T07:14:54Z"},"cvss":{"score":7.8,"severity":"HIGH","version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","provenance":"source","from":"NVD"},"epss":{"score":0.01058,"percentile":0.64395,"date":"2026-10-29","provenance":"source"},"kev":{"dateAdded":"2022-05-23","dueDate":"2022-06-13","ransomware":false,"requiredAction":"Apply updates per vendor instructions.","notes":"https://nvd.nist.gov/vuln/detail/CVE-2021-1048","provenance":"source"},"vulncheckKev":{"dateAdded":"2021-11-06","exploitedFirstSeen":"2021-11-06","ransomware":false,"evidence":[{"url":"https://docs.google.com/spreadsheets/d/1lkNJ0uQwbeC1ZTRrxdtuPLCIl7mlUreoKfSIgajnSyY/edit","date":"2021-11-06"},{"url":"https://www.cisa.gov/sites/default/files/feeds/known_exploited_vulnerabilities.json","date":"2022-05-23"},{"url":"https://blog.talosintelligence.com/mercenary-intellexa-predator/","date":"2023-05-25"},{"url":"https://storage.googleapis.com/gweb-uniblog-publish-prod/documents/Buying_Spying_-_Insights_into_Commercial_Surveillance_Vendors.pdf","date":"2024-02-06"},{"url":"https://www.ox.security/wp-content/uploads/2025/05/The-KEV-Illusion-Separating-True-Threats-from-Pretend-Critical-Risks-v4.pdf","date":"2025-05-30"}],"evidenceTotal":5,"provenance":"source"},"exploited":true,"otx":{"pulseCount":50,"pulses":[{"name":"Actively_Exploited_Kev | Oct 29, 2026","url":"https://otx.alienvault.com/pulse/6ae20c1db17e7057ae7d9ad1","created":"2026-10-28"},{"name":"Actively_Exploited_Kev | Oct 28, 2026","url":"https://otx.alienvault.com/pulse/6ae0ba7e0e2a97ff7b218819","created":"2026-10-27"},{"name":"Actively_Exploited_Kev | Oct 27, 2026","url":"https://otx.alienvault.com/pulse/6adf68b85c3e852f3c111d18","created":"2026-10-26"},{"name":"Actively_Exploited_Kev | Oct 24, 2026","url":"https://otx.alienvault.com/pulse/6adb740e397c3ad4799aa4cd","created":"2026-10-23"},{"name":"Actively_Exploited_Kev | Oct 23, 2026","url":"https://otx.alienvault.com/pulse/6ada236fcfba2dfa730ea482","created":"2026-10-22"},{"name":"Actively_Exploited_Kev | Oct 22, 2026","url":"https://otx.alienvault.com/pulse/6ad8d33a077cbb5cab524d80","created":"2026-10-21"},{"name":"Actively_Exploited_Kev | Oct 21, 2026","url":"https://otx.alienvault.com/pulse/6ad78130c4d1ac2be83a8b6d","created":"2026-10-20"},{"name":"Actively_Exploited_Kev | Oct 20, 2026","url":"https://otx.alienvault.com/pulse/6ad62f63c24a405a3423cc13","created":"2026-10-19"},{"name":"Actively_Exploited_Kev | Oct 19, 2026","url":"https://otx.alienvault.com/pulse/6ad4dda174e5797d0bd238b7","created":"2026-10-18"},{"name":"Actively_Exploited_Kev | Oct 18, 2026","url":"https://otx.alienvault.com/pulse/6ad38c22e1848f8189d1c121","created":"2026-10-17"}],"provenance":"machine"},"cwes":[{"id":"CWE-416","name":"Use After Free"}],"references":[{"url":"https://source.android.com/security/bulletin/2021-11-01","tags":["Patch","Vendor Advisory"]},{"url":"https://source.android.com/security/bulletin/2021-11-01","tags":["Patch","Vendor Advisory"]},{"url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-1048","tags":["Third Party Advisory","US Government Resource"]}],"techniques":[{"id":"T1068","name":"Exploitation for Privilege Escalation","tactics":["privilege-escalation"],"provenance":"ai","basis":"ai-mapping","bases":["ai-mapping"],"basisDetail":"claude-haiku-5-5: Local privilege escalation via kernel memory corruption","mappingType":"exploitation_technique","evidence":[{"from":"description","quote":"could lead to local escalation of privilege","start":110,"end":153}],"model":"claude-haiku-5-5","confidence":"medium","confidenceNote":"AI-mapped from the description (quote-validated, not expert-reviewed)"}],"reports":[],"affected":[],"advisories":[],"euvd":{"id":"EUVD-2021-6515","url":"https://euvd.enisa.europa.eu/vulnerability/EUVD-2021-6515","exploited":true,"exploitedSince":"2022-05-23","provenance":"source"},"exploits":[],"exploitSources":null,"exploitRefs":[],"flow":[{"stage":"exploitation","techniques":["T1068"],"provenance":"ai"}],"timeline":[{"date":"2021-11-06","kind":"exploited-reported","label":"Exploitation first reported (VulnCheck KEV 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0.6440"},{"name":"Named in threat reports","points":0.0,"detail":"0 reports"},{"name":"Public exploit code","points":0.0,"detail":"none found"},{"name":"Mentioned in OTX pulses","points":3.0,"detail":"50 pulses"},{"name":"CVSS severity","points":5.46,"detail":"base score 7.8"},{"name":"End-of-life product","points":0.0,"detail":"supported or unknown"}]},"lineage":{"familyId":"fam-class-android-kernel-cwe-416"}}