{"cve":"CVE-2015-1637","nvd":{"published":"2015-03-06T17:59:00.070","modified":"2026-06-17T00:22:44.653","status":"Modified","description":"Schannel (aka Secure Channel) in Microsoft Windows Server 2003 SP2, Windows Vista SP2, Windows Server 2008 SP2 and R2 SP1, Windows 7 SP1, Windows 8, Windows 8.1, Windows Server 2012 Gold and R2, and Windows RT Gold and 8.1 does not properly restrict TLS state transitions, which makes it easier for remote attackers to conduct cipher-downgrade attacks to EXPORT_RSA ciphers via crafted TLS traffic, related to the \"FREAK\" issue, a different vulnerability than CVE-2015-0204 and CVE-2015-1067.","cvss_v4":null,"cvss_v3":null,"cwes":["CWE-310"],"references":["http://web.archive.org/web/20150321220028/https://freakattack.com/","http://www.securityfocus.com/bid/72965","http://www.securitytracker.com/id/1031833","https://docs.microsoft.com/en-us/security-updates/securitybulletins/2015/ms15-031","https://freakattack.com/"],"products":["microsoft:windows_7","microsoft:windows_8","microsoft:windows_8.1","microsoft:windows_rt","microsoft:windows_rt_8.1","microsoft:windows_server_2003","microsoft:windows_server_2008","microsoft:windows_server_2012","microsoft:windows_vista"],"source":"nvd","synced_at":"2026-10-19T20:35:35.528235705+00:00"},"epss":{"cve":"CVE-2015-1637","score":0.13151,"percentile":0.96361,"date":"2026-10-31"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}