The implementation of digital signatures for JAR files in Mozilla Firefox 4.x through 5, SeaMonkey 2.x before 2.3, and possibly other products does not prevent calls from unsigned JavaScript code to signed code, which allows remote attackers to bypass the Same Origin Policy and gain privileges via a crafted web site, a different vulnerability than CVE-2008-2801.

Mozilla Firefox before 2.0.0.15 and SeaMonkey before 1.1.10 do not properly implement JAR signing, which allows remote attackers to execute arbitrary code via (1) injection of JavaScript into documents within a JAR archive or (2) a JAR archive that uses relative URLs to JavaScript files.