{"id":"CVE-2021-1048","kind":"vulnerability","aliases":["CVE-2021-1048"],"related":[],"title":"Android Kernel: Android Kernel Use-After-Free Vulnerability","description":"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","summary":"A use-after-free bug in the Android kernel lets a local process corrupt freed memory and escalate its privileges. CISA lists it as actively exploited in the wild.","severity":"high","cvss":7.8,"epss":0.01058,"exploited":true,"exploited_at":"2022-05-23T00:00:00+00:00","products":[{"name":"Android Kernel","fixed":[],"affected":"","ecosystem":"vendor"}],"ecosystems":["vendor"],"tags":["android","exploited","infrastructure","mobile-fleet"],"not_affected_if":["patched-device"],"how_to_check":null,"fix":"Apply the Android security patch that addresses CVE-2021-1048, per vendor instructions as CISA requires. Exact patch level: unknown","status":"open","published_at":"2021-12-15T19:15:14+00:00","first_seen_at":"2026-10-23T19:11:52+00:00","triaged_at":"2026-10-23T21:16:03+00:00","updated_at":"2026-10-23T21:57:35+00:00","category":"infrastructure","confidence":0.6,"triage":{"at":"2026-10-23T21:16:03Z","model":"claude-haiku-5-5","output":{"fix":"Apply the Android security patch that addresses CVE-2021-1048, per vendor instructions as CISA requires. Exact patch level: unknown","reach":"local","impact":"high","summary":"A use-after-free bug in the Android kernel lets a local process corrupt freed memory and escalate its privileges. CISA lists it as actively exploited in the wild.","category":"infrastructure","who_cares":["android","mobile-fleet"],"confidence":0.6,"needs_auth":"yes","worst_case":"Attacker gains kernel-level privileges on the device","analyst_note":"Find the affected Android security bulletin and patched build levels for CVE-2021-1048 (source: cisa.gov KEV entry, Android security bulletins).","how_to_check":"unknown","needs_analyst":true,"not_affected_if":["patched-device"],"user_interaction":"no","needs_special_setup":"unknown","severity_if_unknown":"high"},"cost_usd":0.000444,"input_tokens":2800,"output_tokens":328,"severity_before":"unknown"},"analyst_status":null,"analyst_note":null,"search":"'-1048':12A,15A '-2021':11A,14A '204573007references':102C 'a-204573007references':100C 'activ':49B 'addit':85C 'android':1A,3A,16A,18B,32B,97C 'androidvers':96C 'bug':29B 'check':57C 'cisa':45B 'corrupt':38B,67C 'could':76C 'cve':10A,13A 'due':69C 'ep':55C 'escal':42B,80C 'eventpoll.c':60C 'execut':86C 'exploit':19B,50B 'exploitation.product':95C 'fleet':23B 'free':8A,28B,74C 'freed':39B 'id':99C 'infrastructur':20B 'interact':90C 'kernel':2A,4A,17A,33B,104C 'kernelandroid':98C 'lead':77C 'let':34B 'list':46B 'local':36B,79C 'loop':56C 'memori':40B,68C 'mobil':22B 'mobile-fleet':21B 'need':88C,93C 'possibl':64C 'privileg':44B,82C,87C 'proc':58C 'process':37B 'upstream':103C 'use':6A,26B,72C 'use-after-fre':5A,25B 'user':89C 'vulner':9A 'way':65C 'wild':53B","nicknames":[],"mitigations":[],"who_affected":null,"tier":null,"verified":{},"analyst_revisit_at":null,"first_public_at":"2021-12-15T19:15:14+00:00","kev":{"dateAdded":"2022-05-23","dueDate":"2022-06-13","requiredAction":"Apply updates per vendor instructions.","knownRansomwareCampaignUse":"Unknown"},"cvss_vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","cvss_by":"nvd@nist.gov","poc_count":0,"sources":[{"source":"kev","external_id":"CVE-2021-1048","url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog?search_api_fulltext=CVE-2021-1048","severity":null,"published_at":"2022-05-23T00:00:00+00:00","modified_at":null,"first_seen_at":"2026-10-23T19:11:52+00:00","fetched_at":"2026-10-25T12:39:24+00:00","note":null},{"source":"epss","external_id":"CVE-2021-1048","url":"https://api.first.org/data/v1/epss?cve=CVE-2021-1048","severity":null,"published_at":null,"modified_at":null,"first_seen_at":"2026-10-23T19:13:45+00:00","fetched_at":"2026-10-23T19:13:45+00:00","note":null},{"source":"nvd","external_id":"CVE-2021-1048","url":"https://nvd.nist.gov/vuln/detail/CVE-2021-1048","severity":null,"published_at":"2021-12-15T19:15:14+00:00","modified_at":"2026-06-17T03:30:51+00:00","first_seen_at":"2026-10-23T21:57:35+00:00","fetched_at":"2026-10-23T21:57:35+00:00","note":null}],"documents":[],"notice":"Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai"}