{"id":"CVE-2026-121670","kind":"vulnerability","aliases":["CVE-2026-121670"],"related":[],"title":"Windows Overlay Filter race condition lets a local user gain higher privileges","description":"Concurrent execution using shared resource with improper synchronization ('race condition') in Windows Overlay Filter allows an authorized attacker to elevate privileges locally.","summary":"A race condition in the Windows Overlay Filter driver lets an authorized local user win a timing conflict over a shared resource. A successful attack lets that user elevate their privileges on the machine.","severity":"high","cvss":7.0,"epss":null,"exploited":false,"exploited_at":null,"products":[],"ecosystems":[],"tags":["infrastructure","windows"],"not_affected_if":[],"how_to_check":null,"fix":null,"status":"open","published_at":"2026-11-10T19:20:30+00:00","first_seen_at":"2026-11-10T19:25:09+00:00","triaged_at":"2026-11-10T19:51:23+00:00","updated_at":"2026-11-10T19:51:23+00:00","category":"infrastructure","confidence":0.5,"triage":{"at":"2026-11-10T19:51:23Z","model":"claude-haiku-5-5","output":{"fix":"unknown","reach":"local","title":"Windows Overlay Filter race condition lets a local user gain higher privileges","impact":"high","summary":"A race condition in the Windows Overlay Filter driver lets an authorized local user win a timing conflict over a shared resource. A successful attack lets that user elevate their privileges on the machine.","audience":"businesses","category":"infrastructure","nicknames":[],"who_cares":["windows"],"confidence":0.5,"fix_status":"unknown","needs_auth":"yes","worst_case":"local user gains administrator or SYSTEM privileges on the machine","analyst_note":"Find the Microsoft advisory for CVE-2026-121670 to confirm affected Windows builds, the fixed update and any check for the Overlay Filter component.","how_to_check":"- unknown","plain_action":"","product_name":"","needs_analyst":true,"not_affected_if":[],"who_is_affected":"Only Windows machines where a user already has a local account can be attacked; remote attackers without a login cannot reach it directly. The sources do not name the affected Windows builds or whether the overlay filter feature is on by default. unknown","user_interaction":"no","product_ecosystem":"","needs_special_setup":"unknown","severity_if_unknown":"high"},"cost_usd":0.000663,"input_tokens":4504,"output_tokens":426,"severity_before":"high"},"analyst_status":"queued","analyst_note":"Find the Microsoft advisory for CVE-2026-121670 to confirm affected Windows builds, the fixed update and any check for the Overlay Filter component.","search":"'-121670':15A,18A '-2026':14A,17A 'allow':69C 'attack':45B,72C 'author':32B,71C 'concurr':55C 'condit':5A,23B,64C 'conflict':38B 'cve':13A,16A 'driver':29B 'elev':49B,74C 'execut':56C 'filter':3A,28B,68C 'gain':10A 'higher':11A 'improp':61C 'infrastructur':19B 'let':6A,30B,46B 'local':8A,33B,76C 'machin':54B 'overlay':2A,27B,67C 'privileg':12A,51B,75C 'race':4A,22B,63C 'resourc':42B,59C 'share':41B,58C 'success':44B 'synchron':62C 'time':37B 'use':57C 'user':9A,34B,48B 'win':35B 'window':1A,20B,26B,66C","nicknames":[],"mitigations":[],"who_affected":"Only Windows machines where a user already has a local account can be attacked; remote attackers without a login cannot reach it directly. The sources do not name the affected Windows builds or whether the overlay filter feature is on by default. unknown","tier":"B","verified":{},"analyst_revisit_at":null,"fix_status":"none","audience":"businesses","plain_action":null,"pkeys":[],"ptokens":[],"labels":["high","infrastructure","windows"],"campaign_type":null,"search_a":"'-121670':15A,18A '-2026':14A,17A 'condit':5A 'cve':13A,16A 'filter':3A 'gain':10A 'higher':11A 'let':6A 'local':8A 'overlay':2A 'privileg':12A 'race':4A 'user':9A 'window':1A","search_b":"'attack':45B 'author':32B 'condit':23B 'conflict':38B 'driver':29B 'elev':49B 'filter':28B 'infrastructur':19B 'let':30B,46B 'local':33B 'machin':54B 'overlay':27B 'privileg':51B 'race':22B 'resourc':42B 'share':41B 'success':44B 'time':37B 'user':34B,48B 'win':35B 'window':20B,26B","search_c":"'allow':69C 'attack':72C 'author':71C 'concurr':55C 'condit':64C 'elev':74C 'execut':56C 'filter':68C 'improp':61C 'local':76C 'overlay':67C 'privileg':75C 'race':63C 'resourc':59C 'share':58C 'synchron':62C 'use':57C 'window':66C","cause_entry":null,"cause_path":null,"disclosures_checked_at":null,"first_public_at":"2026-11-10T19:20:30+00:00","kev":null,"cvss_vector":"CVSS:3.1/AV:L/AC:H/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-2026-121670","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-121670","severity":null,"published_at":"2026-11-10T19:20:30+00:00","modified_at":"2026-11-10T19:20:30+00:00","first_seen_at":"2026-11-10T19:25:09+00:00","fetched_at":"2026-11-10T19:25:09+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"}