Ubuntu Security Notice USN-2673-1

20th July, 2015

thunderbird vulnerabilities

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

• Ubuntu 15.04
• Ubuntu 14.10
• Ubuntu 14.04 LTS
• Ubuntu 12.04 LTS

Summary

Several security issues were fixed in Thunderbird.

Software description

• thunderbird
  – Mozilla Open Source mail and newsgroup client

Details

Karthikeyan Bhargavan discovered that NSS incorrectly handled state
transitions for the TLS state machine. If a remote attacker were able to
perform a man-in-the-middle attack, this flaw could be exploited to skip
the ServerKeyExchange message and remove the forward-secrecy property.
(CVE-2015-2721)

Bob Clary, Christian Holler, Bobby Holley, and Andrew McCreight discovered
multiple memory safety issues in Thunderbird. If a user were tricked in to
opening a specially crafted website in a browsing context, an attacker
could potentially exploit these to cause a denial of service via
application crash, or execute arbitrary code with the privileges of the
user invoking Thunderbird. (CVE-2015-2724)

Ronald Crane discovered multiple security vulnerabilities. If a user were
tricked in to opening a specially crafted website in a browsing context,
an attacker could potentially exploit these to cause a denial of service
via application crash, or execute arbitrary code with the privileges of
the user invoking Thunderbird. (CVE-2015-2734, CVE-2015-2735,
CVE-2015-2736, CVE-2015-2737, CVE-2015-2738, CVE-2015-2739, CVE-2015-2740)

Matthew Green discovered a DHE key processing issue in NSS where a MITM
could force a server to downgrade TLS connections to 512-bit export-grade
cryptography. An attacker could potentially exploit this to impersonate
the server. (CVE-2015-4000)

Update instructions

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

Ubuntu 15.04:

thunderbird

1:31.8.0+build1-0ubuntu0.15.04.1

Ubuntu 14.10:

thunderbird

1:31.8.0+build1-0ubuntu0.14.10.1

Ubuntu 14.04 LTS:

thunderbird

1:31.8.0+build1-0ubuntu0.14.04.1

Ubuntu 12.04 LTS:

thunderbird

1:31.8.0+build1-0ubuntu0.12.04.1

To update your system, please follow these instructions:
https://wiki.ubuntu.com/Security/Upgrades.

After a standard system update you need to restart Thunderbird to make
all the necessary changes.

References

CVE-2015-2721,

CVE-2015-2724,

CVE-2015-2734,

CVE-2015-2735,

CVE-2015-2736,

CVE-2015-2737,

CVE-2015-2738,

CVE-2015-2739,

CVE-2015-2740,

CVE-2015-4000