Cscope is a developer's tool for browsing source code.
Cscope does not verify the length of file names sourced in #include statements.
A user could be enticed to source a carefully crafted file which will allow the attacker to execute arbitrary code with the permissions of the user running Cscope.
There is no known workaround at this time.
All Cscope users should upgrade to the latest version:
# emerge --sync
# emerge --ask --oneshot --verbose ">=dev-util/cscope-15.5-r6"