7.8 - USN-2519-1

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

- Ubuntu 14.10 - Ubuntu 14.04 LTS - Ubuntu 12.04 LTS - Ubuntu 10.04 LTS

Summary:

Several security issues were fixed in the GNU C Library.

Software Description: - glibc: GNU C Library - eglibc: GNU C Library

Details:

Arnaud Le Blanc discovered that the GNU C Library incorrectly handled file descriptors when resolving DNS queries under high load. This may cause a denial of service in other applications, or an information leak. This issue only affected Ubuntu 10.04 LTS, Ubuntu 12.04 LTS and Ubuntu 14.04 LTS. (CVE-2013-7423)

It was discovered that the GNU C Library incorrectly handled receiving a positive answer while processing the network name when performing DNS resolution. A remote attacker could use this issue to cause the GNU C Library to hang, resulting in a denial of service. (CVE-2014-9402)

Joseph Myers discovered that the GNU C Library wscanf function incorrectly handled memory. A remote attacker could possibly use this issue to cause the GNU C Library to crash, resulting in a denial of service, or possibly execute arbitrary code. This issue only affected Ubuntu 12.04 LTS, Ubuntu 14.04 LTS and Ubuntu 14.10. (CVE-2015-1472, CVE-2015-1473)

Update instructions:

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

Ubuntu 14.10:
libc6 2.19-10ubuntu2.3

Ubuntu 14.04 LTS:
libc6 2.19-0ubuntu6.6

Ubuntu 12.04 LTS:
libc6 2.15-0ubuntu10.11

Ubuntu 10.04 LTS:
libc6 2.11.1-0ubuntu7.21

After a standard system update you need to reboot your computer to make all the necessary changes.

References:
http://www.ubuntu.com/usn/usn-2519-1
CVE-2013-7423, CVE-2014-9402, CVE-2015-1472, CVE-2015-1473

Package Information:
https://launchpad.net/ubuntu/+source/glibc/2.19-10ubuntu2.3
https://launchpad.net/ubuntu/+source/eglibc/2.19-0ubuntu6.6
https://launchpad.net/ubuntu/+source/eglibc/2.15-0ubuntu10.11
https://launchpad.net/ubuntu/+source/eglibc/2.11.1-0ubuntu7.21