{"id":"CVE-2025-59287","kind":"vulnerability","aliases":["CVE-2025-59287"],"related":[],"title":"Deserialization of untrusted data in Windows Server Update Service allows an unauthorized attacker to execute code…","description":"Microsoft Windows Server Update Service (WSUS) contains a deserialization of untrusted data vulnerability that allows for remote code execution.\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 Windows Server Update Services (WSUS) has a deserialization flaw that lets a remote party run code on the server. CISA lists it as actively exploited in the wild.","severity":"critical","cvss":9.8,"epss":null,"exploited":true,"exploited_at":"2025-10-24T00:00:00+00:00","products":[{"name":"Microsoft Windows","fixed":[],"affected":"","ecosystem":"vendor"},{"name":"microsoft windows server 2012","fixed":[],"affected":"","ecosystem":"vendor"},{"name":"microsoft windows server 2012","fixed":[],"affected":"= r2","ecosystem":"vendor"},{"name":"microsoft windows server 2016","fixed":["10.0.14393.8524"],"affected":"< 10.0.14393.8524","ecosystem":"vendor"},{"name":"microsoft windows server 2019","fixed":["10.0.17763.7922"],"affected":"< 10.0.17763.7922","ecosystem":"vendor"},{"name":"microsoft windows server 2022","fixed":["10.0.20348.4297"],"affected":"< 10.0.20348.4297","ecosystem":"vendor"},{"name":"microsoft windows server 2022 23h2","fixed":["10.0.25398.1916"],"affected":"< 10.0.25398.1916","ecosystem":"vendor"},{"name":"microsoft windows server 2025","fixed":["10.0.26100.6905"],"affected":"< 10.0.26100.6905","ecosystem":"vendor"}],"ecosystems":["vendor"],"tags":["exploited","infrastructure","windows","windows-server","wsus"],"not_affected_if":["no-wsus-role"],"how_to_check":null,"fix":"Apply the Microsoft mitigations or patch for CVE-2025-59287 per vendor instructions; if no mitigation is available, stop using WSUS.","status":"open","published_at":"2025-10-14T17:16:11+00:00","first_seen_at":"2026-10-23T19:11:51+00:00","triaged_at":"2026-10-23T20:44:26+00:00","updated_at":"2026-10-23T23:44:51+00:00","category":"infrastructure","confidence":0.6,"triage":{"at":"2026-10-23T20:44:26Z","model":"claude-haiku-5-5","output":{"fix":"Apply the Microsoft mitigations or patch for CVE-2025-59287 per vendor instructions; if no mitigation is available, stop using WSUS.\nunknown","reach":"network","summary":"Microsoft Windows Server Update Services (WSUS) has a deserialization flaw that lets a remote party run code on the server. CISA lists it as actively exploited in the wild.","category":"infrastructure","who_cares":["windows","wsus","windows-server"],"confidence":0.6,"needs_auth":"unknown","worst_case":"Remote attacker runs code on the WSUS server with its privileges.","analyst_note":"Find the Microsoft advisory for CVE-2025-59287 to confirm affected WSUS versions, patch KBs, required auth, and the exact WSUS role check.","how_to_check":"unknown","needs_analyst":true,"not_affected_if":["no-wsus-role"],"user_interaction":"unknown","needs_special_setup":"unknown","severity_if_unknown":"critical"},"cost_usd":0.000431,"input_tokens":2542,"output_tokens":354,"severity_before":"unknown"},"analyst_status":null,"analyst_note":null,"search":"'-01':121C '-2025':18A,21A '-59287':19A,22A '2012':28A,32A '2016':36A '2019':40A '2022':44A,48A '2025':53A '22':120C '23h2':49A 'action':111C 'activ':85B 'allow':10A,104C 'appli':112C 'applic':118C 'attack':13A 'bod':119C 'cisa':81B,109C 'cloud':124C 'code':16A,77B,107C 'contain':96C 'cve':17A,20A 'data':4A,101C 'deseri':1A,69B,98C 'discontinu':127C 'execut':15A,108C 'exploit':54B,86B 'flaw':70B 'follow':117C 'guidanc':122C 'infrastructur':55B 'instruct':116C 'let':72B 'list':82B 'microsoft':23A,25A,29A,33A,37A,41A,45A,50A,61B,90C 'mitig':113C,133C 'parti':75B 'per':114C 'product':131C 'remot':74B,106C 'requir':110C 'run':76B 'server':7A,27A,31A,35A,39A,43A,47A,52A,59B,63B,80B,92C 'servic':9A,65B,94C,125C 'unauthor':12A 'unavail':135C 'untrust':3A,100C 'updat':8A,64B,93C 'use':128C 'vendor':115C 'vulner':102C 'wild':89B 'window':6A,56B,58B,62B,91C 'windows':24A,26A,30A,34A,38A,42A,46A,51A 'windows-serv':57B 'wsus':60B,66B,95C","nicknames":[],"mitigations":[],"who_affected":null,"tier":null,"verified":{},"analyst_revisit_at":null,"first_public_at":"2025-10-14T17:16:11+00:00","kev":{"dateAdded":"2025-10-24","dueDate":"2025-11-14","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":"Unknown"},"cvss_vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","cvss_by":"secure@microsoft.com","poc_count":0,"sources":[{"source":"kev","external_id":"CVE-2025-59287","url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog?search_api_fulltext=CVE-2025-59287","severity":null,"published_at":"2025-10-24T00:00:00+00:00","modified_at":null,"first_seen_at":"2026-10-23T19:11:51+00:00","fetched_at":"2026-10-25T14:39:38+00:00","note":null},{"source":"nvd","external_id":"CVE-2025-59287","url":"https://nvd.nist.gov/vuln/detail/CVE-2025-59287","severity":null,"published_at":"2025-10-14T17:16:11+00:00","modified_at":"2026-06-17T09:45:52+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"}