Original release date: November 14, 2014

Systems Affected

• Microsoft Windows Server 2003 SP2
• Microsoft Windows Vista SP2
• Microsoft Windows Server 2008 SP2
• Microsoft Windows Server 2008 R2 SP1
• Microsoft Windows 7 SP1
• Microsoft Windows 8
• Microsoft Windows 8.1
• Microsoft Windows Server 2012
• Microsoft Windows Server 2012 R2
• Microsoft Windows RT
• Microsoft Windows RT 8.1

Microsoft Windows XP and 2000 may also be affected.

Overview

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

Description

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]

Impact

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

Solution

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

References

• [1] NIST Vulnerability Summary for CVE-2014-6321
• [2] Microsoft Security Bulletin MS14-066 – Critical
• [3] Microsoft, Secure Channel
• [4] Reddit, Microsoft Security Bulletin MS14-066
• [5] Pastebin, SChannelShenanigans
• [6] Winshock.txt

Revision History

• November 14, 2014: Initial Release

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