K16903 : Microsoft Schannel vulnerability CVE-2015-1637

Security Advisory 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.
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CVE-2015-1637
)
Impact
A remote attacker may be able to conduct cipher-downgrade attacks to EXPORT_RSA ciphers by way of crafted Transport Layer Security (TLS) traffic.