USN-352-1: Thunderbird vulnerabilities

25 September 2006

mozilla-thunderbird vulnerabilities

A security issue affects these releases of Ubuntu and its derivatives:

  • Ubuntu 6.06 LTS

Software Description


Various flaws have been reported that allow an attacker to execute arbitrary code with user privileges by tricking the user into opening a malicious email containing JavaScript. Please note that JavaScript is disabled by default for emails, and it is not recommended to enable it. (CVE-2006-4253, CVE-2006-4565, CVE-2006-4566, CVE-2006-4571)

The NSS library did not sufficiently check the padding of PKCS #1 v1.5 signatures if the exponent of the public key is 3 (which is widely used for CAs). This could be exploited to forge valid signatures without the need of the secret key. (CVE-2006-4340)

Jon Oberheide reported a way how a remote attacker could trick users into downloading arbitrary extensions with circumventing the normal SSL certificate check. The attacker would have to be in a position to spoof the victim’s DNS, causing them to connect to sites of the attacker’s choosing rather than the sites intended by the victim. If they gained that control and the victim accepted the attacker’s cert for the Mozilla update site, then the next update check could be hijacked and redirected to the attacker’s site without detection. (CVE-2006-4567)

Georgi Guninski discovered that even with JavaScript disabled, a malicous email could still execute JavaScript when the message is viewed, replied to, or forwarded by putting the script in a remote XBL file loaded by the message. (CVE-2006-4570)

Update instructions

The problem can be corrected by updating your system to the following package versions:

Ubuntu 6.06 LTS
mozilla-thunderbird -

To update your system, please follow these instructions:

After a standard system upgrade you need to restart Thunderbird to effect the necessary changes.