{"id":"CVE-2024-43451","kind":"vulnerability","aliases":["CVE-2024-43451"],"related":[],"title":"NTLM Hash Disclosure Spoofing Vulnerability","description":"Microsoft Windows contains an NTLMv2 hash spoofing vulnerability that could result in disclosing a user's NTLMv2 hash to an attacker via a file open operation. The attacker could then leverage this hash to impersonate that user.\n\nCISA required action: Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.","summary":"Windows can be tricked into sending a user's NTLMv2 password hash to an attacker when a file is opened. The attacker can then use that hash to impersonate the user.","severity":"high","cvss":6.5,"epss":null,"exploited":true,"exploited_at":"2024-11-12T00:00:00+00:00","products":[{"name":"Microsoft Windows","fixed":[],"affected":"","ecosystem":"vendor"},{"name":"microsoft windows 10 1507","fixed":["10.0.10240.20826"],"affected":"< 10.0.10240.20826","ecosystem":"vendor"},{"name":"microsoft windows 10 1607","fixed":["10.0.14393.7515"],"affected":"< 10.0.14393.7515","ecosystem":"vendor"},{"name":"microsoft windows 10 1809","fixed":["10.0.17763.6532"],"affected":"< 10.0.17763.6532","ecosystem":"vendor"},{"name":"microsoft windows 10 21h2","fixed":["10.0.19044.5131"],"affected":"< 10.0.19044.5131","ecosystem":"vendor"},{"name":"microsoft windows 10 22h2","fixed":["10.0.19045.5131"],"affected":"< 10.0.19045.5131","ecosystem":"vendor"},{"name":"microsoft windows 11 22h2","fixed":["10.0.22621.4460"],"affected":"< 10.0.22621.4460","ecosystem":"vendor"},{"name":"microsoft windows 11 23h2","fixed":["10.0.22631.4460"],"affected":"< 10.0.22631.4460","ecosystem":"vendor"},{"name":"microsoft windows 11 24h2","fixed":["10.0.26100.2314"],"affected":"< 10.0.26100.2314","ecosystem":"vendor"},{"name":"microsoft windows server 2008","fixed":[],"affected":"","ecosystem":"vendor"},{"name":"microsoft windows server 2008","fixed":[],"affected":"= r2","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":["10.0.14393.7515"],"affected":"< 10.0.14393.7515","ecosystem":"vendor"},{"name":"microsoft windows server 2019","fixed":["10.0.17763.6532"],"affected":"< 10.0.17763.6532","ecosystem":"vendor"},{"name":"microsoft windows server 2022","fixed":["10.0.20348.2849"],"affected":"< 10.0.20348.2849","ecosystem":"vendor"},{"name":"microsoft windows server 2022 23h2","fixed":["10.0.25398.1251"],"affected":"< 10.0.25398.1251","ecosystem":"vendor"},{"name":"microsoft windows server 2025","fixed":["10.0.26100.2314"],"affected":"< 10.0.26100.2314","ecosystem":"vendor"}],"ecosystems":["vendor"],"tags":["active-directory","exploited","infrastructure","ntlm","windows"],"not_affected_if":["unknown"],"how_to_check":null,"fix":"Apply the Microsoft mitigations for CVE-2024-43451 as published by Microsoft, or apply the Microsoft security update for it; the sources do not name the KB or build.","status":"open","published_at":"2024-11-12T00:00:00+00:00","first_seen_at":"2026-10-23T19:11:51+00:00","triaged_at":"2026-10-23T20:56:14+00:00","updated_at":"2026-10-23T22:29:05+00:00","category":"infrastructure","confidence":0.6,"triage":{"at":"2026-10-23T20:56:14Z","model":"claude-haiku-5-5","output":{"fix":"Apply the Microsoft mitigations for CVE-2024-43451 as published by Microsoft, or apply the Microsoft security update for it; the sources do not name the KB or build.","reach":"network","impact":"high","summary":"Windows can be tricked into sending a user's NTLMv2 password hash to an attacker when a file is opened. The attacker can then use that hash to impersonate the user.","category":"infrastructure","who_cares":["windows","active-directory","ntlm"],"confidence":0.6,"needs_auth":"no","worst_case":"Attacker impersonates a user by replaying their captured NTLMv2 hash.","analyst_note":"Find the Microsoft advisory for CVE-2024-43451 (msrc.microsoft.com) to confirm the patch KB, the mitigation steps and the affected Windows builds, since the sources give none of these.","how_to_check":"unknown","needs_analyst":true,"not_affected_if":["unknown"],"user_interaction":"yes","needs_special_setup":"unknown","severity_if_unknown":"high"},"cost_usd":0.00047,"input_tokens":2852,"output_tokens":369,"severity_before":"unknown"},"analyst_status":null,"analyst_note":null,"search":"'-2024':7A,10A '-43451':8A,11A '10':16A,20A,24A,28A,32A '11':36A,40A,44A '1507':17A '1607':21A '1809':25A '2008':49A,53A '2012':57A,61A '2016':65A '2019':69A '2022':73A,77A '2025':82A '21h2':29A '22h2':33A,37A '23h2':41A,78A '24h2':45A 'action':160C 'activ':84B 'active-directori':83B 'appli':161C 'attack':104B,111B,141C,148C 'cisa':158C 'contain':123C 'could':130C,149C 'cve':6A,9A 'directori':85B 'disclos':133C 'disclosur':3A 'discontinu':167C 'exploit':86B 'file':107B,144C 'hash':2A,101B,116B,126C,138C,153C 'imperson':118B,155C 'infrastructur':87B 'instruct':165C 'leverag':151C 'microsoft':12A,14A,18A,22A,26A,30A,34A,38A,42A,46A,50A,54A,58A,62A,66A,70A,74A,79A,121C 'mitig':162C,173C 'ntlm':1A,88B 'ntlmv2':99B,125C,137C 'open':109B,145C 'oper':146C 'password':100B 'per':163C 'product':171C 'requir':159C 'result':131C 'send':95B 'server':48A,52A,56A,60A,64A,68A,72A,76A,81A 'spoof':4A,127C 'trick':93B 'unavail':175C 'use':114B,168C 'user':97B,120B,135C,157C 'vendor':164C 'via':142C 'vulner':5A,128C 'window':89B,90B,122C 'windows':13A,15A,19A,23A,27A,31A,35A,39A,43A,47A,51A,55A,59A,63A,67A,71A,75A,80A","nicknames":[],"mitigations":[],"who_affected":null,"tier":null,"verified":{},"analyst_revisit_at":null,"first_public_at":"2024-11-12T00:00:00+00:00","kev":{"dateAdded":"2024-11-12","dueDate":"2024-12-03","requiredAction":"Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.","knownRansomwareCampaignUse":"Unknown"},"cvss_vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N","cvss_by":"secure@microsoft.com","poc_count":0,"sources":[{"source":"kev","external_id":"CVE-2024-43451","url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog?search_api_fulltext=CVE-2024-43451","severity":null,"published_at":"2024-11-12T00:00:00+00:00","modified_at":null,"first_seen_at":"2026-10-23T19:11:51+00:00","fetched_at":"2026-10-25T20:35:33+00:00","note":null},{"source":"nvd","external_id":"CVE-2024-43451","url":"https://nvd.nist.gov/vuln/detail/CVE-2024-43451","severity":null,"published_at":"2024-11-12T18:15:22+00:00","modified_at":"2026-06-17T07:51:04+00:00","first_seen_at":"2026-10-23T22:29:05+00:00","fetched_at":"2026-10-23T22:29:05+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"}