CVE 2009-1688
Cross-site scripting (XSS) vulnerability in WebKit in Apple Safari before 4.0, iPhone OS 1.0 through 2.2.1, and iPhone OS for iPod touch 1.1 through 2.2.1 allows remote attackers to inject arbitrary web script or HTML via vectors related to determining a security context through an approach that is not the "HTML 5 standard method."
See the 
CVE page on Mitre.org
for more details.
