Ubuntu Security Notice USN-3068-1

24th August, 2016

libidn vulnerabilities

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

• Ubuntu 16.04 LTS
• Ubuntu 14.04 LTS
• Ubuntu 12.04 LTS

Summary

Several security issues were fixed in Libidn.

Software description

• libidn
  – implementation of IETF IDN specifications

Details

Thijs Alkemade, Gustavo Grieco, Daniel Stenberg, and Nikos
Mavrogiannopoulos discovered that Libidn incorrectly handled invalid UTF-8
characters. A remote attacker could use this issue to cause Libidn to
crash, resulting in a denial of service, or possibly disclose sensitive
memory. This issue only applied to Ubuntu 12.04 LTS and Ubuntu 14.04 LTS.
(CVE-2015-2059)

Hanno Böck discovered that Libidn incorrectly handled certain input. A
remote attacker could possibly use this issue to cause Libidn to crash,
resulting in a denial of service. (CVE-2015-8948, CVE-2016-6262,
CVE-2016-6261, CVE-2016-6263)

Update instructions

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

Ubuntu 16.04 LTS:

libidn11

1.32-3ubuntu1.1

Ubuntu 14.04 LTS:

libidn11

1.28-1ubuntu2.1

Ubuntu 12.04 LTS:

libidn11

1.23-2ubuntu0.1

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

In general, a standard system update will make all the necessary changes.

References

CVE-2015-2059,

CVE-2015-8948,

CVE-2016-6261,

CVE-2016-6262,

CVE-2016-6263

Ubuntu Security Notice USN-3067-1

24th August, 2016

harfbuzz vulnerabilities

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

• Ubuntu 16.04 LTS
• Ubuntu 14.04 LTS

Summary

HarfBuzz could be made to crash or run programs as your login if it
processed specially crafted data.

Software description

• harfbuzz
  – OpenType text shaping engine

Details

Kostya Serebryany discovered that HarfBuzz incorrectly handled memory. A
remote attacker could use this issue to cause HarfBuzz to crash, resulting
in a denial of service, or possibly execute arbitrary code. (CVE-2015-8947)

It was discovered that HarfBuzz incorrectly handled certain length checks.
A remote attacker could use this issue to cause HarfBuzz to crash,
resulting in a denial of service, or possibly execute arbitrary code.
This issue only applied to Ubuntu 16.04 LTS. (CVE-2016-2052)

Update instructions

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

Ubuntu 16.04 LTS:

libharfbuzz0b

1.0.1-1ubuntu0.1

Ubuntu 14.04 LTS:

libharfbuzz0b

0.9.27-1ubuntu1.1

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

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

References

CVE-2015-8947,

CVE-2016-2052