Firefox 0.9, Thunderbird 0.6 and other versions before 0.9, and Mozilla 1.7 before 1.7.5 save temporary files with world-readable permissions, which allows local users to read certain web content or attachments that belong to other users, e.g. content that is managed by helper applications such as PDF.
Exploit prediction scoring system (EPSS) score
EPSS Score 0.001
EPSS Ranking 18.7%