CVE 2007-0778
The page cache feature in Mozilla Firefox before 1.5.0.10 and 2.x before 2.0.0.2, and SeaMonkey before 1.0.8 can generate hash collisions that cause page data to be appended to the wrong page cache, which allows remote attackers to obtain sensitive information or enable further attack vectors when the target page is reloaded from the cache.
See the 
CVE page on Mitre.org
for more details.
