The SSLVerifySignedServerKeyExchange function in libsecurity_ssl/lib/sslKeyExchange.c in the Secure Transport feature in the Data Security component in Apple iOS 6.x before 6.1.6 and 7.x before 7.0.6, Apple TV 6.x before 6.0.2, and Apple OS X 10.9.x before 10.9.2 does not check the signature in a TLS Server Key Exchange message, which allows man-in-the-middle attackers to spoof SSL servers by (1) using an arbitrary private key for the signing step or (2) omitting the signing step.

References

• https://nvd.nist.gov/vuln/detail/CVE-2014-1266
• https://news.ycombinator.com/item?id=7281378
• https://www.cs.columbia.edu/~smb/blog/2014-02/2014-02-23.html
• https://www.cs.columbia.edu/~smb/blog/2014-02/2014-02-24.html
• https://www.imperialviolet.org/2014/02/22/applebug.html
• http://it.slashdot.org/comments.pl?sid=4821073&cid=46310187
• http://support.apple.com/kb/HT6146
• http://support.apple.com/kb/HT6147
• http://support.apple.com/kb/HT6148
• http://support.apple.com/kb/HT6150