{"id":"CVE-2026-33825","kind":"vulnerability","aliases":["CVE-2026-33825"],"related":[],"title":"microsoft defender antimalware platform: Insufficient granularity of access control in Microsoft Defender allows an authorized attacker to elevate privileges…","description":"Microsoft Defender contains an insufficient granularity of access control vulnerability that could allow an authorized attacker to escalate privileges locally.\n\nCISA required action: Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.","summary":"Microsoft Defender contains an access control weakness that lets an already-authorized local user escalate their privileges. CISA lists it as actively exploited, and the catalog tags it with ransomware use.","severity":"high","cvss":7.8,"epss":null,"exploited":true,"exploited_at":"2026-04-22T00:00:00+00:00","products":[{"name":"Microsoft Defender","fixed":[],"affected":"","ecosystem":"vendor"},{"name":"microsoft defender antimalware platform","fixed":["4.18.26030.3011"],"affected":"< 4.18.26030.3011","ecosystem":"vendor"}],"ecosystems":["vendor"],"tags":["exploited","microsoft-defender","other","ransomware","windows"],"not_affected_if":["no-local-user-access"],"how_to_check":null,"fix":"Apply the mitigations Microsoft publishes for CVE-2026-33825, per CISA's required action; the sources do not name a patched version.","status":"open","published_at":"2026-04-14T18:17:35+00:00","first_seen_at":"2026-10-23T19:11:51+00:00","triaged_at":"2026-10-23T20:38:42+00:00","updated_at":"2026-10-23T23:44:51+00:00","category":"other","confidence":0.6,"triage":{"at":"2026-10-23T20:38:42Z","model":"claude-haiku-5-5","output":{"fix":"Apply the mitigations Microsoft publishes for CVE-2026-33825, per CISA's required action; the sources do not name a patched version.","reach":"local","summary":"Microsoft Defender contains an access control weakness that lets an already-authorized local user escalate their privileges. CISA lists it as actively exploited, and the catalog tags it with ransomware use.","category":"other","who_cares":["windows","microsoft-defender"],"confidence":0.6,"needs_auth":"yes","worst_case":"A local user with low privileges gains higher privileges on the machine.","analyst_note":"Find Microsoft's advisory for CVE-2026-33825 to get the affected Defender versions, the patch or mitigation, and a check command.","how_to_check":"unknown","needs_analyst":true,"not_affected_if":["no-local-user-access"],"user_interaction":"no","needs_special_setup":"unknown","severity_if_unknown":"high"},"cost_usd":0.000417,"input_tokens":2535,"output_tokens":327,"severity_before":"unknown"},"analyst_status":null,"analyst_note":null,"search":"'-01':103C '-2026':21A,24A '-33825':22A,25A '22':102C 'access':8A,43B,78C 'action':93C 'activ':61B 'allow':13A,83C 'alreadi':50B 'already-author':49B 'antimalwar':3A 'antimalware':30A 'appli':94C 'applic':100C 'attack':16A,86C 'author':15A,51B,85C 'bod':101C 'catalog':65B 'cisa':57B,91C 'cloud':106C 'contain':41B,73C 'control':9A,44B,79C 'could':82C 'cve':20A,23A 'defend':2A,12A,35B,40B,72C 'defender':27A,29A 'discontinu':109C 'elev':18A 'escal':54B,88C 'exploit':32B,62B 'follow':99C 'granular':6A,76C 'guidanc':104C 'instruct':98C 'insuffici':5A,75C 'let':47B 'list':58B 'local':52B,90C 'microsoft':1A,11A,26A,28A,34B,39B,71C 'microsoft-defend':33B 'mitig':95C,115C 'per':96C 'platform':4A,31A 'privileg':19A,56B,89C 'product':113C 'ransomwar':37B,69B 'requir':92C 'servic':107C 'tag':66B 'unavail':117C 'use':70B,110C 'user':53B 'vendor':97C 'vulner':80C 'weak':45B 'window':38B","nicknames":[],"mitigations":[],"who_affected":null,"tier":null,"verified":{},"analyst_revisit_at":null,"first_public_at":"2026-04-14T18:17:35+00:00","kev":{"dateAdded":"2026-04-22","dueDate":"2026-05-06","requiredAction":"Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.","knownRansomwareCampaignUse":"Known"},"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":"kev","external_id":"CVE-2026-33825","url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog?search_api_fulltext=CVE-2026-33825","severity":null,"published_at":"2026-04-22T00:00:00+00:00","modified_at":null,"first_seen_at":"2026-10-23T19:11:51+00:00","fetched_at":"2026-10-25T10:39:04+00:00","note":null},{"source":"nvd","external_id":"CVE-2026-33825","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-33825","severity":null,"published_at":"2026-04-14T18:17:35+00:00","modified_at":"2026-07-24T22:10:00+00:00","first_seen_at":"2026-10-23T23:44:51+00:00","fetched_at":"2026-10-23T23:44:51+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"}