The Data Access component in Apple iOS before 5 does not properly handle the existence of multiple user accounts on the same mail server, which allows local users to bypass intended access restrictions in opportunistic circumstances by leveraging a different account's cookie.

The Data Security component in Apple iOS before 4.2.10 and 4.3.x before 4.3.5 does not check the basicConstraints parameter during validation of X.509 certificate chains, which allows man-in-the-middle attackers to spoof an SSL server by using a non-CA certificate to sign a certificate for an arbitrary domain.

The queueing primitives in IOMobileFrameBuffer in Apple iOS before 4.2.9 and 4.3.x before 4.3.4 do not properly perform type conversion, which allows local users to gain privileges via a crafted application.

Integer signedness error in psaux/t1decode.c in FreeType before 2.4.6, as used in CoreGraphics in Apple iOS before 4.2.9 and 4.3.x before 4.3.4 and other products, allows remote attackers to execute arbitrary code or cause a denial of service (memory corruption and application crash) via a crafted Type 1 font in a PDF document, as exploited in the wild in July 2011.

Integer overflow in QuickLook, as used in Apple Mac OS X before 10.6.7 and MobileSafari in Apple iOS before 4.2.7 and 4.3.x before 4.3.2, allows remote attackers to execute arbitrary code or cause a denial of service (memory corruption and application crash) via a Microsoft Office document with a crafted size field in the OfficeArtMetafileHeader, related to OfficeArtBlip, as demonstrated on the iPhone by Charlie Miller and Dion Blazakis during a Pwn2Own competition at CanSecWest 2011.

Use-after-free vulnerability in WebKit, as used in Apple Safari before 5.0.5; iOS before 4.3.2 for iPhone, iPod, and iPad; iOS before 4.2.7 for iPhone 4 (CDMA); and possibly other products allows remote attackers to execute arbitrary code by adding children to a WBR tag and then removing the tag, related to text nodes, as demonstrated by Chaouki Bekrar during a Pwn2Own competition at CanSecWest 2011.