Multiple buffer overflows in sharutils 4.2.1 and earlier may allow attackers to execute arbitrary code via (1) long output from wc to shar, or (2) unknown vectors in unshar.
https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A11093
https://bugzilla.fedora.us/show_bug.cgi?id=2155
http://www.securityfocus.com/bid/11298