Category Archives: Ubuntu

Ubuntu Security Notices

USN-2710-1: OpenSSH vulnerabilities

Ubuntu Security Notice USN-2710-1

14th August, 2015

openssh vulnerabilities

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

  • Ubuntu 15.04
  • Ubuntu 14.04 LTS
  • Ubuntu 12.04 LTS

Summary

Several security issues were fixed in OpenSSH.

Software description

  • openssh
    – secure shell (SSH) for secure access to remote machines

Details

Moritz Jodeit discovered that OpenSSH incorrectly handled usernames when
using PAM authentication. If an additional vulnerability were discovered in
the OpenSSH unprivileged child process, this issue could allow a remote
attacker to perform user impersonation. (CVE number pending)

Moritz Jodeit discovered that OpenSSH incorrectly handled context memory
when using PAM authentication. If an additional vulnerability were
discovered in the OpenSSH unprivileged child process, this issue could
allow a remote attacker to bypass authentication or possibly execute
arbitrary code. (CVE number pending)

Jann Horn discovered that OpenSSH incorrectly handled time windows for
X connections. A remote attacker could use this issue to bypass certain
access restrictions. (CVE-2015-5352)

It was discovered that OpenSSH incorrectly handled keyboard-interactive
authentication. In a non-default configuration, a remote attacker could
possibly use this issue to perform a brute-force password attack.
(CVE-2015-5600)

Update instructions

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

Ubuntu 15.04:
openssh-server

1:6.7p1-5ubuntu1.2
Ubuntu 14.04 LTS:
openssh-server

1:6.6p1-2ubuntu2.2
Ubuntu 12.04 LTS:
openssh-server

1:5.9p1-5ubuntu1.6

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-2015-5352,

CVE-2015-5600

USN-2702-2: Ubufox update

Ubuntu Security Notice USN-2702-2

11th August, 2015

ubufox update

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

  • Ubuntu 15.04
  • Ubuntu 14.04 LTS
  • Ubuntu 12.04 LTS

Summary

This update provides compatible packages for Firefox 40.

Software description

  • ubufox
    – Ubuntu modifications for Firefox

Details

USN-2702-1 fixed vulnerabilities in Firefox. This update provides the
corresponding updates for Ubufox.

Original advisory details:

Gary Kwong, Christian Holler, Byron Campen, Tyson Smith, Bobby Holley,
Chris Coulson, and Eric Rahm discovered multiple memory safety issues in
Firefox. If a user were tricked in to opening a specially crafted website,
an attacker could potentially exploit these to cause a denial of service
via application crash, or execute arbitrary code with the privileges of
the user invoking Firefox. (CVE-2015-4473, CVE-2015-4474)

Aki Helin discovered an out-of-bounds read when playing malformed MP3
content in some circumstances. If a user were tricked in to opening a
specially crafted website, an attacker could potentially exploit this to
obtain sensitive information, cause a denial of service via application
crash, or execute arbitrary code with the privileges of the user invoking
Firefox. (CVE-2015-4475)

A use-after-free was discovered during MediaStream playback in some
circumstances. If a user were tricked in to opening a specially crafted
website, an attacker could potentially exploit this to cause a denial of
service via application crash or execute arbitrary code with the
priviliges of the user invoking Firefox. (CVE-2015-4477)

André Bargull discovered that non-configurable properties on javascript
objects could be redefined when parsing JSON. If a user were tricked in to
opening a specially crafted website, an attacker could potentially exploit
this to bypass same-origin restrictions. (CVE-2015-4478)

Multiple integer overflows were discovered in libstagefright. If a user
were tricked in to opening a specially crafted website, an attacker could
potentially exploit these to cause a denial of service via application
crash, or execute arbitrary code with the privileges of the user invoking
Firefox. (CVE-2015-4479, CVE-2015-4480, CVE-2015-4493)

Jukka Jylänki discovered a crash that occurs because javascript does not
properly gate access to Atomics or SharedArrayBuffers in some
circumstances. If a user were tricked in to opening a specially crafted
website, an attacker could potentially exploit this to cause a denial of
service. (CVE-2015-4484)

Abhishek Arya discovered 2 buffer overflows in libvpx when decoding
malformed WebM content in some circumstances. If a user were tricked in
to opening a specially crafted website, an attacker could potentially
exploit these to cause a denial of service via application crash, or
execute arbitrary code with the privileges of the user invoking Firefox.
(CVE-2015-4485, CVE-2015-4486)

Ronald Crane reported 3 security issues. If a user were tricked in to
opening a specially crafted website, an attacker could potentially
exploit these, in combination with another security vulnerability, to
cause a denial of service via application crash, or execute arbitrary
code with the privileges of the user invoking Firefox. (CVE-2015-4487,
CVE-2015-4488, CVE-2015-4489)

Christoph Kerschbaumer discovered an issue with Mozilla’s implementation
of Content Security Policy (CSP), which could allow for a more permissive
usage in some cirucumstances. An attacker could potentially exploit this
to conduct cross-site scripting (XSS) attacks. (CVE-2015-4490)

Gustavo Grieco discovered a heap overflow in gdk-pixbuf. If a user were
tricked in to opening a specially crafted website, an attacker could
potentially exploit this to cause a denial of service via application
crash or execute arbitrary code with the priviliges of the user invoking
Firefox. (CVE-2015-4491)

Looben Yang discovered a use-after-free when using XMLHttpRequest with
shared workers in some circumstances. If a user were tricked in to opening
a specially crafted website, an attacker could potentially exploit this to
cause a denial of service via application crash or execute arbitrary code
with the priviliges of the user invoking Firefox. (CVE-2015-4492)

Update instructions

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

Ubuntu 15.04:
xul-ext-ubufox

3.1-0ubuntu0.15.04.1
Ubuntu 14.04 LTS:
xul-ext-ubufox

3.1-0ubuntu0.14.04.1
Ubuntu 12.04 LTS:
xul-ext-ubufox

3.1-0ubuntu0.12.04.1

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

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

References

LP: 1483858

USN-2702-1: Firefox vulnerabilities

Ubuntu Security Notice USN-2702-1

11th August, 2015

firefox vulnerabilities

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

  • Ubuntu 15.04
  • Ubuntu 14.04 LTS
  • Ubuntu 12.04 LTS

Summary

Firefox could be made to crash or run programs as your login if it
opened a malicious website.

Software description

  • firefox
    – Mozilla Open Source web browser

Details

Gary Kwong, Christian Holler, Byron Campen, Tyson Smith, Bobby Holley,
Chris Coulson, and Eric Rahm discovered multiple memory safety issues in
Firefox. If a user were tricked in to opening a specially crafted website,
an attacker could potentially exploit these to cause a denial of service
via application crash, or execute arbitrary code with the privileges of
the user invoking Firefox. (CVE-2015-4473, CVE-2015-4474)

Aki Helin discovered an out-of-bounds read when playing malformed MP3
content in some circumstances. If a user were tricked in to opening a
specially crafted website, an attacker could potentially exploit this to
obtain sensitive information, cause a denial of service via application
crash, or execute arbitrary code with the privileges of the user invoking
Firefox. (CVE-2015-4475)

A use-after-free was discovered during MediaStream playback in some
circumstances. If a user were tricked in to opening a specially crafted
website, an attacker could potentially exploit this to cause a denial of
service via application crash or execute arbitrary code with the
priviliges of the user invoking Firefox. (CVE-2015-4477)

André Bargull discovered that non-configurable properties on javascript
objects could be redefined when parsing JSON. If a user were tricked in to
opening a specially crafted website, an attacker could potentially exploit
this to bypass same-origin restrictions. (CVE-2015-4478)

Multiple integer overflows were discovered in libstagefright. If a user
were tricked in to opening a specially crafted website, an attacker could
potentially exploit these to cause a denial of service via application
crash, or execute arbitrary code with the privileges of the user invoking
Firefox. (CVE-2015-4479, CVE-2015-4480, CVE-2015-4493)

Jukka Jylänki discovered a crash that occurs because javascript does not
properly gate access to Atomics or SharedArrayBuffers in some
circumstances. If a user were tricked in to opening a specially crafted
website, an attacker could potentially exploit this to cause a denial of
service. (CVE-2015-4484)

Abhishek Arya discovered 2 buffer overflows in libvpx when decoding
malformed WebM content in some circumstances. If a user were tricked in
to opening a specially crafted website, an attacker could potentially
exploit these to cause a denial of service via application crash, or
execute arbitrary code with the privileges of the user invoking Firefox.
(CVE-2015-4485, CVE-2015-4486)

Ronald Crane reported 3 security issues. If a user were tricked in to
opening a specially crafted website, an attacker could potentially
exploit these, in combination with another security vulnerability, to
cause a denial of service via application crash, or execute arbitrary
code with the privileges of the user invoking Firefox. (CVE-2015-4487,
CVE-2015-4488, CVE-2015-4489)

Christoph Kerschbaumer discovered an issue with Mozilla’s implementation
of Content Security Policy (CSP), which could allow for a more permissive
usage in some cirucumstances. An attacker could potentially exploit this
to conduct cross-site scripting (XSS) attacks. (CVE-2015-4490)

Gustavo Grieco discovered a heap overflow in gdk-pixbuf. If a user were
tricked in to opening a specially crafted website, an attacker could
potentially exploit this to cause a denial of service via application
crash or execute arbitrary code with the priviliges of the user invoking
Firefox. (CVE-2015-4491)

Looben Yang discovered a use-after-free when using XMLHttpRequest with
shared workers in some circumstances. If a user were tricked in to opening
a specially crafted website, an attacker could potentially exploit this to
cause a denial of service via application crash or execute arbitrary code
with the priviliges of the user invoking Firefox. (CVE-2015-4492)

Update instructions

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

Ubuntu 15.04:
firefox

40.0+build4-0ubuntu0.15.04.1
Ubuntu 14.04 LTS:
firefox

40.0+build4-0ubuntu0.14.04.1
Ubuntu 12.04 LTS:
firefox

40.0+build4-0ubuntu0.12.04.1

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

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

References

CVE-2015-4473,

CVE-2015-4474,

CVE-2015-4475,

CVE-2015-4477,

CVE-2015-4478,

CVE-2015-4479,

CVE-2015-4480,

CVE-2015-4484,

CVE-2015-4485,

CVE-2015-4486,

CVE-2015-4487,

CVE-2015-4488,

CVE-2015-4489,

CVE-2015-4490,

CVE-2015-4491,

CVE-2015-4492,

CVE-2015-4493

USN-2707-1: Firefox vulnerability

Ubuntu Security Notice USN-2707-1

7th August, 2015

firefox vulnerability

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

  • Ubuntu 15.04
  • Ubuntu 14.04 LTS
  • Ubuntu 12.04 LTS

Summary

Firefox could be made to expose sensitive information from local files.

Software description

  • firefox
    – Mozilla Open Source web browser

Details

Cody Crews discovered a way to violate the same-origin policy to inject
script in to a non-privileged part of the PDF viewer. If a user were
tricked in to opening a specially crafted website, an attacker could
exploit this to read sensitive information from local files.
(CVE-2015-4495)

Update instructions

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

Ubuntu 15.04:
firefox

39.0.3+build2-0ubuntu0.15.04.1
Ubuntu 14.04 LTS:
firefox

39.0.3+build2-0ubuntu0.14.04.1
Ubuntu 12.04 LTS:
firefox

39.0.3+build2-0ubuntu0.12.04.1

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

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

References

CVE-2015-4495

USN-2706-1: OpenJDK 6 vulnerabilities

Ubuntu Security Notice USN-2706-1

6th August, 2015

openjdk-6 vulnerabilities

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

  • Ubuntu 12.04 LTS

Summary

Several security issues were fixed in OpenJDK 6.

Software description

  • openjdk-6
    – Open Source Java implementation

Details

Several vulnerabilities were discovered in the OpenJDK JRE related to
information disclosure, data integrity, and availability. An attacker
could exploit these to cause a denial of service or expose sensitive
data over the network. (CVE-2015-2590, CVE-2015-2628, CVE-2015-4731,
CVE-2015-4732, CVE-2015-4733, CVE-2015-4760, CVE-2015-4748)

Several vulnerabilities were discovered in the cryptographic components
of the OpenJDK JRE. An attacker could exploit these to expose sensitive
data over the network. (CVE-2015-2601, CVE-2015-2808, CVE-2015-4000,
CVE-2015-2625, CVE-2015-2613)

As a security improvement, this update modifies OpenJDK behavior to
disable RC4 TLS/SSL cipher suites by default.

As a security improvement, this update modifies OpenJDK behavior to
reject DH key sizes below 768 bits by default, preventing a possible
downgrade attack.

Several vulnerabilities were discovered in the OpenJDK JRE related
to information disclosure. An attacker could exploit these to expose
sensitive data over the network. (CVE-2015-2621, CVE-2015-2632)

A vulnerability was discovered with how the JNDI component of the
OpenJDK JRE handles DNS resolutions. A remote attacker could exploit
this to cause a denial of service. (CVE-2015-4749)

Update instructions

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

Ubuntu 12.04 LTS:
icedtea-6-jre-cacao

6b36-1.13.8-0ubuntu1~12.04
icedtea-6-jre-jamvm

6b36-1.13.8-0ubuntu1~12.04
openjdk-6-jdk

6b36-1.13.8-0ubuntu1~12.04
openjdk-6-source

6b36-1.13.8-0ubuntu1~12.04
openjdk-6-jre

6b36-1.13.8-0ubuntu1~12.04
openjdk-6-jre-headless

6b36-1.13.8-0ubuntu1~12.04
openjdk-6-jre-zero

6b36-1.13.8-0ubuntu1~12.04
openjdk-6-jre-lib

6b36-1.13.8-0ubuntu1~12.04

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

This update uses a new upstream release, which includes additional
bug fixes. After a standard system update you need to restart any
Java applications or applets to make all the necessary changes.

References

CVE-2015-2590,

CVE-2015-2601,

CVE-2015-2621,

CVE-2015-2625,

CVE-2015-2628,

CVE-2015-2632,

CVE-2015-2808,

CVE-2015-4000,

CVE-2015-4731,

CVE-2015-4732,

CVE-2015-4733,

CVE-2015-4748,

CVE-2015-4749,

CVE-2015-4760

USN-2705-1: Keystone vulnerabilities

Ubuntu Security Notice USN-2705-1

5th August, 2015

python-keystoneclient, python-keystonemiddleware vulnerabilities

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

  • Ubuntu 15.04
  • Ubuntu 14.04 LTS

Summary

Keystone could be made to expose sensitive information over the
network.

Software description

  • python-keystoneclient
    – Client library for OpenStack Identity API

  • python-keystonemiddleware
    – Client library for OpenStack Identity API

Details

Qin Zhao discovered Keystone disabled certification verification when
the “insecure” option is set in a paste configuration (paste.ini)
file regardless of the value, which allows remote attackers to conduct
man-in-the-middle attacks via a crafted certificate. (CVE-2014-7144)

Brant Knudson discovered Keystone disabled certification verification when
the “insecure” option is set in a paste configuration (paste.ini)
file regardless of the value, which allows remote attackers to conduct
man-in-the-middle attacks via a crafted certificate. (CVE-2015-1852)

Update instructions

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

Ubuntu 15.04:
python-keystonemiddleware

1.5.0-0ubuntu1.1
python-keystoneclient

1:1.2.0-0ubuntu1.1
Ubuntu 14.04 LTS:
python-keystoneclient

1:0.7.1-ubuntu1.2

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

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

References

CVE-2014-7144,

CVE-2015-1852

USN-2704-1: Swift vulnerabilities

Ubuntu Security Notice USN-2704-1

5th August, 2015

swift vulnerabilities

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

  • Ubuntu 15.04
  • Ubuntu 14.04 LTS
  • Ubuntu 12.04 LTS

Summary

Several security issues were fixed in Swift.

Software description

  • swift
    – OpenStack distributed virtual object store

Details

Rajaneesh Singh discovered Swift does not properly enforce metadata
limits. An attacker could abuse this issue to store more metadata than
allowed by policy. (CVE-2014-7960)

Clay Gerrard discovered Swift allowed users to delete the latest version
of object regardless of object permissions when allow_version is
configured. An attacker could use this issue to delete objects.
(CVE-2015-1856)

Update instructions

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

Ubuntu 15.04:
swift

2.2.2-0ubuntu1.3
Ubuntu 14.04 LTS:
swift

1.13.1-0ubuntu1.2
Ubuntu 12.04 LTS:
swift

1.4.8-0ubuntu2.5

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

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

References

CVE-2014-7960,

CVE-2015-1856

USN-2703-1: Cinder vulnerability

Ubuntu Security Notice USN-2703-1

5th August, 2015

cinder vulnerability

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

  • Ubuntu 15.04

Summary

Cinder could be made to access unintended files over the network by an
authenticated user.

Software description

  • cinder
    – OpenStack storage service

Details

Bastian Blank discovered that Cinder guessed image formats based on
untrusted data. An attacker could use this to read arbitrary files from
the Cinder host.

Update instructions

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

Ubuntu 15.04:
python-cinder

1:2015.1.0-0ubuntu1.1

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

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

References

CVE-2015-1851

USN-2677-1: Oxide vulnerabilities

Ubuntu Security Notice USN-2677-1

4th August, 2015

oxide-qt vulnerabilities

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

  • Ubuntu 15.04
  • Ubuntu 14.04 LTS

Summary

Several security issues were fixed in Oxide.

Software description

  • oxide-qt
    – Web browser engine library for Qt (QML plugin)

Details

An uninitialized value issue was discovered in ICU. If a user were
tricked in to opening a specially crafted website, an attacker could
potentially exploit this to cause a denial of service. (CVE-2015-1270)

A use-after-free was discovered in the GPU process implementation in
Chromium. If a user were tricked in to opening a specially crafted
website, an attacker could potentially exploit this to cause a denial of
service via application crash, or execute arbitrary code with the
privileges of the user invoking the program. (CVE-2015-1272)

A use-after-free was discovered in the IndexedDB implementation in
Chromium. If a user were tricked in to opening a specially crafted
website, an attacker could potentially exploit this to cause a denial of
service via application crash, or execute arbitrary code with the
privileges of the user invoking the program. (CVE-2015-1276)

A use-after-free was discovered in the accessibility implemetation in
Chromium. If a user were tricked in to opening a specially crafted
website, an attacker could potentially exploit this to cause a denial of
service via application crash, or execute arbitrary code with the
privileges of the user invoking the program. (CVE-2015-1277)

A memory corruption issue was discovered in Skia. If a user were tricked
in to opening a specially crafted website, an attacker could potentially
exploit this to cause a denial of service via renderer crash, or execute
arbitrary code with the privileges of the sandboxed render process.
(CVE-2015-1280)

It was discovered that Blink did not properly determine the V8 context of
a microtask in some circumstances. If a user were tricked in to opening a
specially crafted website, an attacker could potentially exploit this to
bypass Content Security Policy (CSP) restrictions. (CVE-2015-1281)

Multiple integer overflows were discovered in Expat. If a user were
tricked in to opening a specially crafted website, an attacker could
potentially exploit this to cause a denial of service via application
crash, or execute arbitrary code with the privileges of the user invoking
the program. (CVE-2015-1283)

It was discovered that Blink did not enforce a page’s maximum number of
frames in some circumstances, resulting in a use-after-free. If a user
were tricked in to opening a specially crafted website, an attacker could
potentially exploit this to cause a denial of service via renderer crash,
or execute arbitrary code with the privileges of the sandboxed render
process. (CVE-2015-1284)

It was discovered that the XSS auditor in Blink did not properly choose a
truncation point. If a user were tricked in to opening a specially crafted
website, an attacker could potentially exploit this to obtain sensitive
information. (CVE-2015-1285)

An issue was discovered in the CSS implementation in Blink. If a user were
tricked in to opening a specially crafted website, an attacker could
potentially exploit this to bypass same-origin restrictions.
(CVE-2015-1287)

Multiple security issues were discovered in Chromium. If a user were
tricked in to opening a specially crafted website, an attacker could
potentially exploit these to read uninitialized memory, cause a denial
of service via application crash or execute arbitrary code with the
privileges of the user invoking the program. (CVE-2015-1289)

A use-after-free was discovered in oxide::qt::URLRequestDelegatedJob in
some circumstances. If a user were tricked in to opening a specially
crafted website, an attacker could potentially exploit this to cause a
denial of service via application crash, or execute arbitrary code with
the privileges of the user invoking the program. (CVE-2015-1329)

A crash was discovered in the regular expression implementation in V8 in
some circumstances. If a user were tricked in to opening a specially
crafted website, an attacker could potentially exploit this to cause a
denial of service. (CVE-2015-5605)

Update instructions

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

Ubuntu 15.04:
liboxideqtcore0

1.8.4-0ubuntu0.15.04.1
Ubuntu 14.04 LTS:
liboxideqtcore0

1.8.4-0ubuntu0.14.04.2

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-2015-1270,

CVE-2015-1272,

CVE-2015-1276,

CVE-2015-1277,

CVE-2015-1280,

CVE-2015-1281,

CVE-2015-1283,

CVE-2015-1284,

CVE-2015-1285,

CVE-2015-1287,

CVE-2015-1289,

CVE-2015-1329,

CVE-2015-5605,

LP: 1466208

USN-2696-1: OpenJDK 7 vulnerabilities

Ubuntu Security Notice USN-2696-1

30th July, 2015

openjdk-7 vulnerabilities

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

  • Ubuntu 15.04
  • Ubuntu 14.04 LTS

Summary

Several security issues were fixed in OpenJDK 7.

Software description

  • openjdk-7
    – Open Source Java implementation

Details

Several vulnerabilities were discovered in the OpenJDK JRE related to
information disclosure, data integrity, and availability. An attacker
could exploit these to cause a denial of service or expose sensitive
data over the network. (CVE-2015-2590, CVE-2015-2628, CVE-2015-4731,
CVE-2015-4732, CVE-2015-4733, CVE-2015-4760, CVE-2015-4748)

Several vulnerabilities were discovered in the cryptographic components
of the OpenJDK JRE. An attacker could exploit these to expose sensitive
data over the network. (CVE-2015-2601, CVE-2015-2808, CVE-2015-4000,
CVE-2015-2625, CVE-2015-2613)

As a security improvement, this update modifies OpenJDK behavior to
disable RC4 TLS/SSL cipher suites by default.

As a security improvement, this update modifies OpenJDK behavior to
reject DH key sizes below 768 bits by default, preventing a possible
downgrade attack.

Several vulnerabilities were discovered in the OpenJDK JRE related
to information disclosure. An attacker could exploit these to expose
sensitive data over the network. (CVE-2015-2621, CVE-2015-2632)

A vulnerability was discovered with how the JNDI component of the
OpenJDK JRE handles DNS resolutions. A remote attacker could exploit
this to cause a denial of service. (CVE-2015-4749)

Update instructions

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

Ubuntu 15.04:
openjdk-7-jre-zero

7u79-2.5.6-0ubuntu1.15.04.1
icedtea-7-jre-jamvm

7u79-2.5.6-0ubuntu1.15.04.1
openjdk-7-jre-lib

7u79-2.5.6-0ubuntu1.15.04.1
openjdk-7-jdk

7u79-2.5.6-0ubuntu1.15.04.1
openjdk-7-jre-headless

7u79-2.5.6-0ubuntu1.15.04.1
openjdk-7-jre

7u79-2.5.6-0ubuntu1.15.04.1
Ubuntu 14.04 LTS:
openjdk-7-jre-zero

7u79-2.5.6-0ubuntu1.14.04.1
icedtea-7-jre-jamvm

7u79-2.5.6-0ubuntu1.14.04.1
openjdk-7-jre-lib

7u79-2.5.6-0ubuntu1.14.04.1
openjdk-7-jdk

7u79-2.5.6-0ubuntu1.14.04.1
openjdk-7-jre-headless

7u79-2.5.6-0ubuntu1.14.04.1
openjdk-7-jre

7u79-2.5.6-0ubuntu1.14.04.1

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

This update uses a new upstream release, which includes additional
bug fixes. After a standard system update you need to restart any
Java applications or applets to make all the necessary changes.

References

CVE-2015-2590,

CVE-2015-2601,

CVE-2015-2613,

CVE-2015-2621,

CVE-2015-2625,

CVE-2015-2628,

CVE-2015-2632,

CVE-2015-2808,

CVE-2015-4000,

CVE-2015-4731,

CVE-2015-4732,

CVE-2015-4733,

CVE-2015-4748,

CVE-2015-4749,

CVE-2015-4760,

https://wiki.ubuntu.com/SecurityTeam/KnowledgeBase/LogJam