The squidGuard.cgi program is vulnerable to a reflected cross site scripting vulnerability in the blocking script squidGuard.cgi. The vulnerability is triggered when a user clicks a link to a blocked site where the url has scripting instructions added (CVE-2015-8936).
In Mageia's squidguard package, both /var/www/cgi-bin/squidGuard.cgi and /usr/share/squidGuard-1.4/samples/squidGuard.cgi were affected.
Note that it is highly recommended that any remaining users of this package switch to ufdbguard, which has better compatibility with current versions of Squid.