[USN-3739-2] libxml2 vulnerabilities

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Ubuntu Security Notice USN-3739-2
August 14, 2018

libxml2 vulnerabilities
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A security issue affects these releases of Ubuntu and its derivatives:

- Ubuntu 12.04 ESM

Summary:

Several security issues were fixed in libxml2.

Software Description:
- libxml2: GNOME XML library

Details:

USN-3739-1 fixed a vulnerability in libxml2. This update provides
the corresponding update for Ubuntu 12.04.

Original advisory details:

 Matias Brutti discovered that libxml2 incorrectly handled certain XML
 files. An attacker could possibly use this issue to expose sensitive
 information. (CVE-2016-9318)

 It was discovered that libxml2 incorrectly handled certain files.
 An attacker could possibly use this issue to cause a denial of
 service. (CVE-2018-14404)

Update instructions:

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

Ubuntu 12.04 ESM:
  libxml2                         2.7.8.dfsg-5.1ubuntu4.21
  libxml2-utils                   2.7.8.dfsg-5.1ubuntu4.21
  python-libxml2                  2.7.8.dfsg-5.1ubuntu4.21

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

References:
  https://usn.ubuntu.com/usn/usn-3739-2
  https://usn.ubuntu.com/usn/usn-3739-1
  CVE-2016-9318, CVE-2018-14404