=========================================================================Ubuntu Security Notice USN-3424-2
October 10, 2017

libxml2 vulnerabilities
=========================================================================
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-3424-1 fixed several vulnerabilities in libxml2. This update
provides the corresponding update for Ubuntu 12.04 ESM.

Original advisory details:

 It was discovered that a type confusion error existed in libxml2. An
 attacker could use this to specially construct XML data that
 could cause a denial of service or possibly execute arbitrary
 code. (CVE-2017-0663)

 It was discovered that libxml2 did not properly validate parsed entity
 references. An attacker could use this to specially construct XML
 data that could expose sensitive information. (CVE-2017-7375)

 It was discovered that a buffer overflow existed in libxml2 when
 handling HTTP redirects. An attacker could use this to specially
 construct XML data that could cause a denial of service or possibly
 execute arbitrary code. (CVE-2017-7376)

 Marcel Böhme and Van-Thuan Pham discovered a buffer overflow in
 libxml2 when handling elements. An attacker could use this to
 specially construct XML data that could cause a denial of service or
 possibly execute arbitrary code. (CVE-2017-9047)

 Marcel Böhme and Van-Thuan Pham discovered a buffer overread
 in libxml2 when handling elements. An attacker could use this
 to specially construct XML data that could cause a denial of
 service. (CVE-2017-9048)

 Marcel Böhme and Van-Thuan Pham discovered multiple buffer overreads
 in libxml2 when handling parameter-entity references. An attacker
 could use these to specially construct XML data that could cause a
 denial of service. (CVE-2017-9049, CVE-2017-9050)

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-5.1ubuntu4.18

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

References:
  https://ubuntu.com/security/notices/USN-3424-2
  https://ubuntu.com/security/notices/USN-3424-1
  CVE-2017-0663, CVE-2017-7375, CVE-2017-7376, CVE-2017-9047,
  CVE-2017-9048, CVE-2017-9049, CVE-2017-9050