{"id":"CVE-2021-31201","kind":"vulnerability","aliases":["CVE-2021-31201"],"related":[],"title":"Microsoft Enhanced Cryptographic Provider: Microsoft Enhanced Cryptographic Provider Privilege Escalation Vulnerability","description":"Microsoft Enhanced Cryptographic Provider contains an unspecified vulnerability that allows for privilege escalation.\n\nCISA required action: Apply updates per vendor instructions.","summary":"Microsoft Enhanced Cryptographic Provider, a Windows cryptographic component, contains an unspecified flaw that lets a local user escalate privileges. An attacker with a foothold on the machine can gain higher privileges, and CISA lists it as actively exploited.","severity":"high","cvss":7.8,"epss":0.02617,"exploited":true,"exploited_at":"2021-11-03T00:00:00+00:00","products":[{"name":"Microsoft Enhanced Cryptographic Provider","fixed":[],"affected":"","ecosystem":"vendor"}],"ecosystems":["vendor"],"tags":["exploited","infrastructure","self-hosted","windows"],"not_affected_if":["unpatched-fleets-not-in-scope"],"how_to_check":null,"fix":"Apply the Microsoft security update for CVE-2021-31201 per vendor instructions (CISA required action); the specific KB or patched build is not given in the sources.","status":"open","published_at":"2021-06-08T23:15:08+00:00","first_seen_at":"2026-10-23T19:11:53+00:00","triaged_at":"2026-10-23T21:39:44+00:00","updated_at":"2026-10-23T21:57:35+00:00","category":"infrastructure","confidence":0.6,"triage":{"at":"2026-10-23T21:39:44Z","model":"claude-haiku-5-5","output":{"fix":"Apply the Microsoft security update for CVE-2021-31201 per vendor instructions (CISA required action); the specific KB or patched build is not given in the sources.","reach":"local","impact":"high","summary":"Microsoft Enhanced Cryptographic Provider, a Windows cryptographic component, contains an unspecified flaw that lets a local user escalate privileges. An attacker with a foothold on the machine can gain higher privileges, and CISA lists it as actively exploited.","category":"infrastructure","who_cares":["windows","self-hosted"],"confidence":0.6,"needs_auth":"yes","worst_case":"local attacker gains higher privileges on the Windows host","analyst_note":"Find the Microsoft Security Response Center advisory for CVE-2021-31201 to confirm affected Windows builds and the patch KB; the sources here do not name them.","how_to_check":"unknown","needs_analyst":true,"not_affected_if":["unpatched-fleets-not-in-scope"],"user_interaction":"no","needs_special_setup":"no","severity_if_unknown":"high"},"cost_usd":0.000475,"input_tokens":2853,"output_tokens":380,"severity_before":"unknown"},"analyst_status":"queued","analyst_note":"Find the Microsoft Security Response Center advisory for CVE-2021-31201 to confirm affected Windows builds and the patch KB; the sources here do not name them.","search":"'-2021':13A,16A '-31201':14A,17A 'action':81C 'activ':64B 'allow':75C 'appli':82C 'attack':48B 'cisa':60B,79C 'compon':35B 'contain':36B,70C 'cryptograph':3A,7A,30B,34B,68C 'cryptographic':20A 'cve':12A,15A 'enhanc':2A,6A,29B,67C 'enhanced':19A 'escal':10A,45B,78C 'exploit':22B,65B 'flaw':39B 'foothold':51B 'gain':56B 'higher':57B 'host':26B 'infrastructur':23B 'instruct':86C 'let':41B 'list':61B 'local':43B 'machin':54B 'microsoft':1A,5A,18A,28B,66C 'per':84C 'privileg':9A,46B,58B,77C 'provid':4A,8A,31B,69C 'provider':21A 'requir':80C 'self':25B 'self-host':24B 'unspecifi':38B,72C 'updat':83C 'user':44B 'vendor':85C 'vulner':11A,73C 'window':27B,33B","nicknames":[],"mitigations":[],"who_affected":null,"tier":null,"verified":{},"analyst_revisit_at":null,"first_public_at":"2021-06-08T23:15:08+00:00","kev":{"dateAdded":"2021-11-03","dueDate":"2021-11-17","requiredAction":"Apply updates per vendor instructions.","knownRansomwareCampaignUse":"Unknown"},"cvss_vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N","cvss_by":"secure@microsoft.com","poc_count":0,"sources":[{"source":"kev","external_id":"CVE-2021-31201","url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog?search_api_fulltext=CVE-2021-31201","severity":null,"published_at":"2021-11-03T00:00:00+00:00","modified_at":null,"first_seen_at":"2026-10-23T19:11:53+00:00","fetched_at":"2026-10-25T21:35:52+00:00","note":null},{"source":"epss","external_id":"CVE-2021-31201","url":"https://api.first.org/data/v1/epss?cve=CVE-2021-31201","severity":null,"published_at":null,"modified_at":null,"first_seen_at":"2026-10-23T19:13:44+00:00","fetched_at":"2026-10-23T19:13:44+00:00","note":null},{"source":"nvd","external_id":"CVE-2021-31201","url":"https://nvd.nist.gov/vuln/detail/CVE-2021-31201","severity":null,"published_at":"2021-06-08T23:15:08+00:00","modified_at":"2026-06-17T03:51:26+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"}