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 does not initialize a pointer during handling of a Cascading Style Sheets (CSS) attr function call with a large numerical argument, which allows remote attackers to execute arbitrary code or cause a denial of service (memory corruption and application crash) via a crafted HTML document.
Exploitability
AV:NAC:MAu:NImpact
C:CI:CA:C9.3/AV:N/AC:M/Au:N/C:C/I:C/A:C