==========================================================================
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:

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

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

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

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

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

A Marcel BAPhme and Van-Thuan Pham discovered multiple buffer overreads
A in libxml2 when handling parameter-entity references. An attacker
A could use these to specially construct XML data that could cause a
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:
A  libxml2A A A A A A A A A A A A A A A A A A A A A A A A A 2.7.8.dfsg-5.1ubuntu4.18

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

References:
A  https://www.ubuntu.com/usn/usn-3424-2
A  https://www.ubuntu.com/usn/usn-3424-1
A  CVE-2017-0663, CVE-2017-7375, CVE-2017-7376, CVE-2017-9047,
A  CVE-2017-9048, CVE-2017-9049, CVE-2017-9050