7.5 - USN-157-1

A security issue affects the following Ubuntu releases:

Ubuntu 4.10 (Warty Warthog) Ubuntu 5.04 (Hoary Hedgehog)

The following packages are affected:

mozilla-thunderbird mozilla-thunderbird-enigmail

The problem can be corrected by upgrading the affected package to version 1.0.6-0ubuntu04.10 (for Ubuntu 4.10), or 1.0.6-0ubuntu05.04 (for Ubuntu 5.04). You need to restart Thunderbird after a standard system upgrade to effect the necessary changes.

The current Enigmail plugin is not compatible any more with the Thunderbird version shipped in this security update, so the mozilla-thunderbird-enigmail package needs to be updated as well. An update is already available for Ubuntu 5.04, and will be delivered shortly for Ubuntu 4.10.

Details follow:

Vladimir V. Perepelitsa discovered a bug in Thunderbird's handling of anonymous functions during regular expression string replacement. A malicious HTML email could exploit this to capture a random block of client memory. (CAN-2005-0989)

Georgi Guninski discovered that the types of certain XPInstall related JavaScript objects were not sufficiently validated when they were called. This could be exploited by malicious HTML email content to crash Thunderbird or even execute arbitrary code with the privileges of the user. (CAN-2005-1159)

Thunderbird did not properly verify the values of XML DOM nodes. By tricking the user to perform a common action like clicking on a link or opening the context menu, a malicious HTML email could exploit this to execute arbitrary JavaScript code with the full privileges of the user. (CAN-2005-1160)

A variant of the attack described in CAN-2005-1160 (see USN-124-1) was discovered. Additional checks were added to make sure Javascript eval and script objects are run with the privileges of the context that created them, not the potentially elevated privilege of the context calling them. (CAN-2005-1532)

Scripts in XBL controls from web content continued to be run even when Javascript was disabled. This could be combined with most script-based exploits to attack people running vulnerable versions who thought disabling Javascript would protect them. (CAN-2005-2261)

The function for version comparison in the addons installer did not properly verify the type of its argument. By passing specially crafted Javascript objects to it, a malicious web site could crash Thunderbird and possibly even execute arbitrary code with the privilege of the user account Thunderbird runs in. (CAN-2005-2265)

The XHTML DOM node handler did not take namespaces into account when verifying node types based on their names. For example, an XHTML email could contain an tag with malicious contents, which would then be processed as the standard trusted HTML tag. By tricking an user to view a malicious email, this could be exploited to execute attacker-specified code with the full privileges of the user. (CAN-2005-2269)

It was discovered that some objects were not created appropriately. This allowed malicious web content scripts to trace back the creation chain until they found a privileged object and execute code with higher privileges than allowed by the current site. (CAN-2005-2270)

Javier Fernández-Sanguino Peña discovered that the run-mozilla.sh script created temporary files in an unsafe way when running with 'debugging' enabled. This could allow a symlink attack to create or overwrite arbitrary files with the privileges of the user invoking the program. (CAN-2005-2353)

The update for Ubuntu 4.10 (Warty Warthog) also fixes several less critical vulnerabilities which are not present in the Ubuntu 5.04 version. (MFSA-2005-02 to MFSA-2005-30; please see the following web site for details: http://www.mozilla.org/projects/security/known-vulnerabilities.html). We apologize for the huge delay of this update; we changed our update strategy for Mozilla products to make sure that such long delays will not happen again.