Firefox Sage extension 1.3.8 and earlier allows remote attackers to execute arbitrary Javascript in the local context via an RSS feed with an img tag containing the script followed by an extra trailing ">", which Sage modifies to close the img element before the malicious script.

Firefox Sage extension 1.3.8 and earlier allows remote attackers to execute arbitrary Javascript in the local context via an RSS feed with an img tag containing the script followed by an extra trailing ">", which Sage modifies to close the img element before the malicious script.