Squid 2.5.STABLE9 and earlier does not trigger a fatal error when it identifies missing or invalid ACLs in the http_access configuration, which could lead to less restrictive ACLs than intended by the administrator.
distro.conectiva.com.br/atualizacoes/?id=a&anuncio=000948
fedoranews.org/updates/FEDORA--.shtml
www.debian.org/security/2005/dsa-721
www.redhat.com/support/errata/RHSA-2005-415.html
www.squid-cache.org/bugs/show_bug.cgi?id=1255
www.squid-cache.org/Versions/v2/2.5/bugs/#squid-2.5.STABLE9-acl_error
oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A10513