SHA-1 is not collision resistant, which makes it easier for context-dependent attackers to conduct spoofing attacks, as demonstrated by attacks on the use of SHA-1 in TLS 1.2. NOTE: this CVE exists to provide a common identifier for referencing this SHA-1 issue; the existence of an identifier is not, by itself, a technology recommendation.
https://www.schneier.com/blog/archives/2005/08/new_cryptanalyt.html
https://www.schneier.com/blog/archives/2005/02/sha1_broken.html
https://sites.google.com/site/itstheshappening
https://security.googleblog.com/2017/02/announcing-first-sha1-collision.html
https://security.googleblog.com/2015/12/an-update-on-sha-1-certificates-in.html
https://kc.mcafee.com/corporate/index?page=content&id=SB10340
http://www.securityfocus.com/bid/12577
http://www.cwi.nl/news/2017/cwi-and-google-announce-first-collision-industry-security-standard-sha-1