{"id":"CVE-2020-0646","kind":"vulnerability","aliases":["CVE-2020-0646"],"related":[],"title":"Microsoft .NET Framework: Microsoft .NET Framework Remote Code Execution Vulnerability","description":"A remote code execution vulnerability exists when the Microsoft .NET Framework fails to validate input properly, aka '.NET Framework Remote Code Execution Injection Vulnerability'.","summary":"Microsoft .NET Framework mishandles input validation, which lets a crafted request run code on the machine. Attackers who can reach the affected application can run code with its privileges.","severity":"critical","cvss":10.0,"epss":0.99222,"exploited":true,"exploited_at":"2021-11-03T00:00:00+00:00","products":[{"name":"Microsoft .NET Framework","fixed":[],"affected":"","ecosystem":"vendor"}],"ecosystems":["vendor"],"tags":[".net-framework","exploited","runtime","self-hosted","windows"],"not_affected_if":["no-dotnet-framework","patched-systems"],"how_to_check":null,"fix":"Apply the Microsoft security update for CVE-2020-0646 for your .NET Framework versions, per vendor instructions (CISA required action).","status":"open","published_at":"2020-01-14T23:15:33+00:00","first_seen_at":"2026-10-23T19:11:53+00:00","triaged_at":"2026-10-23T21:39:14+00:00","updated_at":"2026-10-23T21:57:34+00:00","category":"runtime","confidence":0.6,"triage":{"at":"2026-10-23T21:39:14Z","model":"claude-haiku-5-5","output":{"fix":"Apply the Microsoft security update for CVE-2020-0646 for your .NET Framework versions, per vendor instructions (CISA required action).","reach":"network","impact":"high","summary":"Microsoft .NET Framework mishandles input validation, which lets a crafted request run code on the machine. Attackers who can reach the affected application can run code with its privileges.","category":"runtime","who_cares":["windows",".net-framework","self-hosted"],"confidence":0.6,"needs_auth":"unknown","worst_case":"Attacker runs arbitrary code on the affected Windows machine remotely.","analyst_note":"Find the affected .NET Framework versions, the KB patch list and the exact attack surface in Microsoft's advisory for CVE-2020-0646 and the CISA KEV entry.","how_to_check":"unknown","needs_analyst":true,"not_affected_if":["patched-systems","no-dotnet-framework"],"user_interaction":"unknown","needs_special_setup":"unknown","severity_if_unknown":"critical"},"cost_usd":0.000463,"input_tokens":2821,"output_tokens":362,"severity_before":"unknown"},"analyst_status":"queued","analyst_note":"Find the affected .NET Framework versions, the KB patch list and the exact attack surface in Microsoft's advisory for CVE-2020-0646 and the CISA KEV entry.","search":"'-0646':13A,16A '-2020':12A,15A 'affect':50B 'aka':74C 'applic':51B 'attack':45B 'code':8A,41B,54B,60C,78C 'craft':38B 'cve':11A,14A 'execut':9A,61C,79C 'exist':63C 'exploit':23B 'fail':69C 'framework':3A,6A,19A,22B,31B,68C,76C 'host':27B 'inject':80C 'input':33B,72C 'let':36B 'machin':44B 'microsoft':1A,4A,17A,29B,66C 'mishandl':32B 'net':2A,5A,18A,21B,30B,67C,75C 'net-framework':20B 'privileg':57B 'proper':73C 'reach':48B 'remot':7A,59C,77C 'request':39B 'run':40B,53B 'runtim':24B 'self':26B 'self-host':25B 'valid':34B,71C 'vulner':10A,62C,81C 'window':28B","nicknames":[],"mitigations":[],"who_affected":null,"tier":null,"verified":{},"analyst_revisit_at":null,"first_public_at":"2020-01-14T23:15:33+00:00","kev":{"dateAdded":"2021-11-03","dueDate":"2022-05-03","requiredAction":"Apply updates per vendor instructions.","knownRansomwareCampaignUse":"Unknown"},"cvss_vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","cvss_by":"nvd@nist.gov","poc_count":0,"sources":[{"source":"kev","external_id":"CVE-2020-0646","url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog?search_api_fulltext=CVE-2020-0646","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":"2026-10-25T16:39:50+00:00","note":null},{"source":"epss","external_id":"CVE-2020-0646","url":"https://api.first.org/data/v1/epss?cve=CVE-2020-0646","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-2020-0646","url":"https://nvd.nist.gov/vuln/detail/CVE-2020-0646","severity":null,"published_at":"2020-01-14T23:15:33+00:00","modified_at":"2026-06-17T02:46:15+00:00","first_seen_at":"2026-10-23T21:57:34+00:00","fetched_at":"2026-10-23T21:57:34+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"}