The context implementation in WebKit, as used in Google Chrome before 10.0.648.127, allows remote attackers to cause a denial of service or possibly have unspecified other impact via unknown vectors that lead to a "stale pointer."
https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A14089
https://exchange.xforce.ibmcloud.com/vulnerabilities/65965
http://www.vupen.com/english/advisories/2011/0628
http://www.securityfocus.com/bid/46785
http://googlechromereleases.blogspot.com/2011/03/chrome-stable-release.html