Use-after-free vulnerability in the PDF functionality in Google Chrome before 21.0.1180.75 allows remote attackers to cause a denial of service or possibly have unspecified other impact via a crafted document.
https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A14788
http://googlechromereleases.blogspot.com/2012/08/stable-channel-update.html
http://code.google.com/p/chromium/issues/detail?id=137957