Microsoft Secure Channel (Schannel) Vulnerability (CVE-2014-6321)

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Alert Code

Systems Affected

  • Microsoft Windows Vista, 7, 8, 8.1, RT, and RT 8.1
  • Microsoft Server 2003, Server 2008, Server 2008 R2, Server 2012, and Server 2012 R2

Microsoft Windows XP and 2000 may also be affected.


A critical vulnerability in Microsoft Windows systems could allow a remote attacker to execute arbitrary code via specially crafted network traffic.[1]

Microsoft Secure Channel (Schannel) is a security package that provides SSL and TLS on Microsoft Windows platforms.[2, 3] Due to a flaw in Schannel, a remote attacker could execute arbitrary code on both client and server applications.[1]

It may be possible for exploitation to occur without authentication and via unsolicited network traffic. According to Microsoft MS14-066, there are no known mitigations or workarounds.[2]

Microsoft patches are typically reverse-engineered and exploits developed in a matter of days or weeks.[4] An anonymous Pastebin user has threatened to publish an exploit on Friday, November 14, 2014.[5]


This flaw allows a remote attacker to execute arbitrary code and fully compromise vulnerable systems.[6]


Microsoft has released Security Bulletin MS14-066 to address this vulnerability in supported operating systems.[2]



November 14, 2014: Initial Release

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