A local user can rename or delete arbitrary files owned by root in Linux Security.
It is possible for a local non-root user to cause arbitrary system files to be renamed or deleted, leading to a permanent corruption (DoS) of the operating system or to disabled antivirus software. This requires that an attacker has gained prior access to a non-privileged user account on the machine. This vulnerability affects F-Secure Linux Security 11-series and F-Secure Linux Security 64.
Technical details are available from the researcher's website:
Note: No known attacks have been reported or observed in the wild.