{"id":"CVE-2026-108403","kind":"vulnerability","aliases":["CVE-2026-108403"],"related":[],"title":"Windows Kernel: use-after-free lets a local user gain higher privileges","description":"Use after free in Windows Kernel allows an authorized attacker to elevate privileges locally.","summary":"A use-after-free bug in the Windows kernel lets an attacker who already has a local account raise their privileges. The sources do not say which Windows versions are affected or how the flaw is triggered.","severity":"high","cvss":7.8,"epss":null,"exploited":false,"exploited_at":null,"products":[],"ecosystems":[],"tags":["infrastructure","kernel","windows"],"not_affected_if":[],"how_to_check":null,"fix":null,"status":"open","published_at":"2026-11-10T19:18:07+00:00","first_seen_at":"2026-11-10T19:24:22+00:00","triaged_at":"2026-11-10T19:42:28+00:00","updated_at":"2026-11-10T19:42:28+00:00","category":"infrastructure","confidence":0.6,"triage":{"at":"2026-11-10T19:42:28Z","model":"claude-haiku-5-5","output":{"fix":"unknown","reach":"local","title":"Windows Kernel: use-after-free lets a local user gain higher privileges","impact":"high","summary":"A use-after-free bug in the Windows kernel lets an attacker who already has a local account raise their privileges. The sources do not say which Windows versions are affected or how the flaw is triggered.","audience":"businesses","category":"infrastructure","nicknames":[],"who_cares":["windows","kernel"],"confidence":0.6,"fix_status":"unknown","needs_auth":"yes","worst_case":"Local attacker gains SYSTEM-level control of the machine","analyst_note":"Check the Microsoft Security Response Center advisory for CVE-2026-108403 for affected Windows builds and the patch.","how_to_check":"- unknown","plain_action":"","product_name":"","needs_analyst":true,"not_affected_if":[],"who_is_affected":"Anyone running an affected Windows version where a local user account can be used by an attacker. The sources do not name the affected Windows versions, so the scope is unknown.","user_interaction":"unknown","product_ecosystem":"","needs_special_setup":"unknown","severity_if_unknown":"high"},"cost_usd":0.000647,"input_tokens":4476,"output_tokens":398,"severity_before":"high"},"analyst_status":"queued","analyst_note":"Check the Microsoft Security Response Center advisory for CVE-2026-108403 for affected Windows builds and the patch.","search":"'-108403':16A,19A '-2026':15A,18A 'account':41B 'affect':54B 'allow':67C 'alreadi':37B 'attack':35B,70C 'author':69C 'bug':28B 'cve':14A,17A 'elev':72C 'flaw':58B 'free':6A,27B,63C 'gain':11A 'higher':12A 'infrastructur':20B 'kernel':2A,21B,32B,66C 'let':7A,33B 'local':9A,40B,74C 'privileg':13A,44B,73C 'rais':42B 'say':49B 'sourc':46B 'trigger':60B 'use':4A,25B,61C 'use-after-fre':3A,24B 'user':10A 'version':52B 'window':1A,22B,31B,51B,65C","nicknames":[],"mitigations":[],"who_affected":"Anyone running an affected Windows version where a local user account can be used by an attacker. The sources do not name the affected Windows versions, so the scope is unknown.","tier":"B","verified":{},"analyst_revisit_at":null,"fix_status":"none","audience":"businesses","plain_action":null,"pkeys":[],"ptokens":[],"labels":["high","infrastructure","kernel","windows"],"campaign_type":null,"search_a":"'-108403':16A,19A '-2026':15A,18A 'cve':14A,17A 'free':6A 'gain':11A 'higher':12A 'kernel':2A 'let':7A 'local':9A 'privileg':13A 'use':4A 'use-after-fre':3A 'user':10A 'window':1A","search_b":"'account':41B 'affect':54B 'alreadi':37B 'attack':35B 'bug':28B 'flaw':58B 'free':27B 'infrastructur':20B 'kernel':21B,32B 'let':33B 'local':40B 'privileg':44B 'rais':42B 'say':49B 'sourc':46B 'trigger':60B 'use':25B 'use-after-fre':24B 'version':52B 'window':22B,31B,51B","search_c":"'allow':67C 'attack':70C 'author':69C 'elev':72C 'free':63C 'kernel':66C 'local':74C 'privileg':73C 'use':61C 'window':65C","cause_entry":null,"cause_path":null,"disclosures_checked_at":null,"first_public_at":"2026-11-10T19:18:07+00:00","kev":null,"cvss_vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","cvss_by":"secure@microsoft.com","poc_count":0,"sources":[{"source":"nvd","external_id":"CVE-2026-108403","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-108403","severity":null,"published_at":"2026-11-10T19:18:07+00:00","modified_at":"2026-11-10T19:18:07+00:00","first_seen_at":"2026-11-10T19:24:22+00:00","fetched_at":"2026-11-10T19:24:22+00:00","note":null}],"documents":[],"disclosures":[],"exploit_sources":[],"notice":"Free to read, with fair use of about 60 pages a minute. For higher limits or API access: sales@infrastack.ai"}