About the security content of iOS 5.0.1 Software Update

This document describes the security content of iOS 5.0.1.

This document describes the security content of iOS 5.0.1, which can be downloaded and installed using iTunes.

For the protection of our customers, Apple does not disclose, discuss, or confirm security issues until a full investigation has occurred and any necessary patches or releases are available. To learn more about Apple Product Security, see the Apple Product Security website.

For information about the Apple Product Security PGP Key, see "How to use the Apple Product Security PGP Key."

Where possible, CVE IDs are used to reference the vulnerabilities for further information.

To learn about other Security Updates, see "Apple Security Updates".

iOS 5.0.1 Software Update

• CFNetwork

  Available for: iOS 3.0 through 5.0 for iPhone 3GS, iPhone 4 and iPhone 4S, iOS 3.1 through 5.0 for iPod touch (3rd generation) and later, iOS 3.2 through 5.0 for iPad, iOS 4.3 through 5.0 for iPad 2

  Impact: Visiting a maliciously crafted website may lead to the disclosure of sensitive information

  Description: An issue existed in CFNetwork's handling of maliciously crafted URLs. When accessing a maliciously crafted HTTP or HTTPS URL, CFNetwork could navigate to an incorrect server.

  CVE-ID

  CVE-2011-3246 : Erling Ellingsen of Facebook

• CoreGraphics

  Available for: iOS 3.0 through 5.0 for iPhone 3GS, iPhone 4 and iPhone 4S, iOS 3.1 through 5.0 for iPod touch (3rd generation) and later, iOS 3.2 through 5.0 for iPad, iOS 4.3 through 5.0 for iPad 2

  Impact: Viewing a document containing a maliciously crafted font may lead to arbitrary code execution

  Description: Multiple memory corruption issues existed in FreeType, the most serious of which may lead to arbitrary code execution when processing a maliciously crafted font.

  CVE-ID

  CVE-2011-3439 : Apple

• Data Security

  Available for: iOS 3.0 through 5.0 for iPhone 3GS, iPhone 4 and iPhone 4S, iOS 3.1 through 5.0 for iPod touch (3rd generation) and later, iOS 3.2 through 5.0 for iPad, iOS 4.3 through 5.0 for iPad 2

  Impact: An attacker with a privileged network position may intercept user credentials or other sensitive information

  Description: Two certificate authorities in the list of trusted root certificates have independently issued intermediate certificates to DigiCert Malaysia. DigiCert Malaysia has issued certificates with weak keys that it is unable to revoke. An attacker with a privileged network position could intercept user credentials or other sensitive information intended for a site with a certificate issued by DigiCert Malaysia. This issue is addressed by configuring default system trust settings so that DigiCert Malaysia's certificates are not trusted. We would like to acknowledge Bruce Morton of Entrust, Inc. for reporting this issue.

• Kernel

  Available for: iOS 3.0 through 5.0 for iPhone 3GS, iPhone 4 and iPhone 4S, iOS 3.1 through 5.0 for iPod touch (3rd generation) and later, iOS 3.2 through 5.0 for iPad, iOS 4.3 through 5.0 for iPad 2

  Impact: An application may execute unsigned code

  Description: A logic error existed in the mmap system call's checking of valid flag combinations. This issue may lead to a bypass of codesigning checks. This issue does not affect devices running iOS prior to version 4.3.

  CVE-ID

  CVE-2011-3442 : Charlie Miller of Accuvant Labs

• libinfo

  Available for: iOS 3.0 through 5.0 for iPhone 3GS, iPhone 4 and iPhone 4S, iOS 3.1 through 5.0 for iPod touch (3rd generation) and later, iOS 3.2 through 5.0 for iPad, iOS 4.3 through 5.0 for iPad 2

  Impact: Visiting a maliciously crafted website may lead to the disclosure of sensitive information

  Description: An issue existed in libinfo's handling of DNS name lookups. When resolving a maliciously crafted hostname, libinfo could return an incorrect result.

  CVE-ID

  CVE-2011-3441 : Erling Ellingsen of Facebook, Per Johansson of Blocket AB

• Passcode Lock

  Available for: iOS 4.3 through 5.0 for iPad 2

  Impact: A person with physical access to a locked iPad 2 may be able to access some of the user's data

  Description: When a Smart Cover is opened while iPad 2 is confirming power off in the locked state, the iPad does not request a passcode. This allows some access to the iPad, but data protected by Data Protection is inaccessible and apps cannot be launched.

  CVE-ID

  CVE-2011-3440