Secunia issued an advisory today over multiple "highly critical" vulnerabilities in Mozilla Firefox.
Malware authors can exploit the flaws to bypass security restrictions, conduct cross-site scripting attacks, reveal sensitive information and possibly compromise a user's system, the advisory said.
Users should update to the latest version, 1.5.0.1.
Firefox released that update Wednesday, saying on its website that the new version includes improved stability, fixes for a number of memory leaks and other security enhancements.
