The SessionService::GetLastSession function in browser/sessions/session_service.cc in Google Chrome before 38.0.2125.101 allows remote attackers to cause a denial of service (use-after-free) or possibly have unspecified other impact via vectors that leverage "type confusion" for callback processing.
http://googlechromereleases.blogspot.com/2014/10/stable-channel-update.html
http://rhn.redhat.com/errata/RHSA-2014-1626.html