{"id":"CVE-2020-1350","kind":"vulnerability","aliases":["CVE-2020-1350"],"related":[],"title":"Microsoft Windows: Microsoft Windows DNS Server Remote Code Execution Vulnerability","description":"Microsoft Windows DNS Servers fail to properly handle requests, allowing an attacker to perform remote code execution in the context of the Local System Account. The vulnerability is also known under the moniker of SIGRed.\n\nCISA required action: Apply updates per vendor instructions.","summary":"Windows DNS Server mishandles certain requests, letting a remote attacker run code as the Local System account. The flaw is known as SIGRed and is listed by CISA as actively exploited.","severity":"critical","cvss":10.0,"epss":0.96721,"exploited":true,"exploited_at":"2021-11-03T00:00:00+00:00","products":[{"name":"Microsoft Windows","fixed":[],"affected":"","ecosystem":"vendor"}],"ecosystems":["vendor"],"tags":["active-directory","dns-server","exploited","infrastructure","windows","windows-server"],"not_affected_if":["no-windows-dns-server-role"],"how_to_check":null,"fix":"Apply the Microsoft update for CVE-2020-1350 per vendor instructions (CISA KEV action); the specific KB number is not in the sources.","status":"open","published_at":"2020-07-14T23:15:13+00:00","first_seen_at":"2026-10-23T19:11:53+00:00","triaged_at":"2026-10-23T21:43:26+00:00","updated_at":"2026-10-23T21:57:34+00:00","category":"infrastructure","confidence":0.8,"triage":{"at":"2026-10-23T21:43:26Z","model":"claude-haiku-5-5","output":{"fix":"Apply the Microsoft update for CVE-2020-1350 per vendor instructions (CISA KEV action); the specific KB number is not in the sources.","reach":"network","impact":"high","summary":"Windows DNS Server mishandles certain requests, letting a remote attacker run code as the Local System account. The flaw is known as SIGRed and is listed by CISA as actively exploited.","category":"infrastructure","who_cares":["windows","windows-server","dns-server","active-directory"],"confidence":0.8,"needs_auth":"no","worst_case":"Remote attacker runs code as SYSTEM on the DNS server","analyst_note":"Find the Microsoft advisory and the patched KB numbers for CVE-2020-1350 and a detection command for the DNS Server role; the sources do not give them.","how_to_check":"unknown","needs_analyst":true,"not_affected_if":["no-windows-dns-server-role"],"user_interaction":"no","needs_special_setup":"yes","severity_if_unknown":"critical"},"cost_usd":0.000464,"input_tokens":2854,"output_tokens":357,"severity_before":"unknown"},"analyst_status":"queued","analyst_note":"Find the Microsoft advisory and the patched KB numbers for CVE-2020-1350 and a detection command for the DNS Server role; the sources do not give them.","search":"'-1350':13A,16A '-2020':12A,15A 'account':47B,86C 'action':99C 'activ':20B,60B 'active-directori':19B 'allow':71C 'also':90C 'appli':100C 'attack':40B,73C 'certain':35B 'cisa':58B,97C 'code':8A,42B,77C 'context':81C 'cve':11A,14A 'directori':21B 'dns':5A,23B,32B,64C 'dns-server':22B 'execut':9A,78C 'exploit':25B,61B 'fail':66C 'flaw':49B 'handl':69C 'infrastructur':26B 'instruct':104C 'known':51B,91C 'let':37B 'list':56B 'local':45B,84C 'microsoft':1A,3A,17A,62C 'mishandl':34B 'monik':94C 'per':102C 'perform':75C 'proper':68C 'remot':7A,39B,76C 'request':36B,70C 'requir':98C 'run':41B 'server':6A,24B,30B,33B,65C 'sigr':53B,96C 'system':46B,85C 'updat':101C 'vendor':103C 'vulner':10A,88C 'window':2A,4A,27B,29B,31B,63C 'windows':18A 'windows-serv':28B","nicknames":[],"mitigations":[],"who_affected":null,"tier":null,"verified":{},"analyst_revisit_at":null,"first_public_at":"2020-07-14T23:15:13+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:C/C:H/I:H/A:H","cvss_by":"nvd@nist.gov","poc_count":0,"sources":[{"source":"kev","external_id":"CVE-2020-1350","url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog?search_api_fulltext=CVE-2020-1350","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":"2026-10-25T11:39:18+00:00","note":null},{"source":"epss","external_id":"CVE-2020-1350","url":"https://api.first.org/data/v1/epss?cve=CVE-2020-1350","severity":null,"published_at":null,"modified_at":null,"first_seen_at":"2026-10-23T19:13:43+00:00","fetched_at":"2026-10-23T19:13:43+00:00","note":null},{"source":"nvd","external_id":"CVE-2020-1350","url":"https://nvd.nist.gov/vuln/detail/CVE-2020-1350","severity":null,"published_at":"2020-07-14T23:15:13+00:00","modified_at":"2026-06-17T03:01:10+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"}