[Security] Bump nokogiri from 1.6.5 to 1.6.8.1

[dependabot-preview]

Bumps nokogiri from 1.6.5 to 1.6.8.1. This update includes security fixes.

Vulnerabilities fixed

Denial of service or RCE from libxml2 and libxslt
Nokogiri is affected by series of vulnerabilities in libxml2 and libxslt,
which are libraries Nokogiri depends on. It was discovered that libxml2 and
libxslt incorrectly handled certain malformed documents, which can allow
malicious users to cause issues ranging from denial of service to remote code
execution attacks.

For more information, the Ubuntu Security Notice is a good start:
http://www.ubuntu.com/usn/usn-2994-1/

Patched versions: [">= 1.6.8"]
Unaffected versions: ["< 1.6.0"]

Nokogiri gem contains several vulnerabilities in libxml2
Nokogiri version 1.6.7.1 has been released, pulling in several upstream
patches to the vendored libxml2 to address the following CVEs:

CVE-2015-5312
CVSS v2 Base Score: 7.1 (HIGH)
The xmlStringLenDecodeEntities function in parser.c in libxml2
before 2.9.3 does not properly prevent entity expansion, which
allows context-dependent attackers to cause a denial of
service (CPU consumption) via crafted XML data, a different
vulnerability than CVE-2014-3660.

CVE-2015-7497
CVSS v2 Base Score: 5.0 (MEDIUM)
Heap-based buffer overflow in the xmlDictComputeFastQKey
function in dict.c in libxml2 before 2.9.3 allows
context-dependent attackers to cause a denial of service via
unspecified vectors.

CVE-2015-7498
CVSS v2 Base Score: 5.0 (MEDIUM)
Heap-based buffer overflow in the xmlParseXmlDecl function in
parser.c in libxml2 before 2.9.3 allows context-dependent
attackers to cause a denial of service via unspecified vectors
related to extracting errors after an encoding conversion
failure.

CVE-2015-7499
CVSS v2 Base Score: 5.0 (MEDIUM)
Heap-based buffer overflow in the xmlGROW function in parser.c
in libxml2 before 2.9.3 allows context-dependent attackers to
obtain sensitive process memory information via unspecified
vectors.

CVE-2015-7500
CVSS v2 Base Score: 5.0 (MEDIUM)
The xmlParseMisc function in parser.c in libxml2 before 2.9.3
allows context-dependent attackers to cause a denial of
service (out-of-bounds heap read) via unspecified vectors
related to incorrect entities boundaries and start tags.

CVE-2015-8241
CVSS v2 Base Score: 6.4 (MEDIUM)
The xmlNextChar function in libxml2 2.9.2 does not properly
check the state, which allows context-dependent attackers to
cause a denial of service (heap-based buffer over-read and
application crash) or obtain sensitive information via crafted
XML data.

CVE-2015-8242
CVSS v2 Base Score: 5.8 (MEDIUM)
The xmlSAX2TextNode function in SAX2.c in the push interface in
the HTML parser in libxml2 before 2.9.3 allows
context-dependent attackers to cause a denial of
service (stack-based buffer over-read and application crash) or
obtain sensitive information via crafted XML data.

CVE-2015-8317
CVSS v2 Base Score: 5.0 (MEDIUM)
The xmlParseXMLDecl function in parser.c in libxml2 before
2.9.3 allows context-dependent attackers to obtain sensitive
information via an (1) unterminated encoding value or (2)
incomplete XML declaration in XML data, which triggers an
out-of-bounds heap read.

Patched versions: [">= 1.6.7.1"]
Unaffected versions: ["< 1.6.0"]

Nokogiri gem contains a heap-based buffer overflow vulnerability in libxml2
Nokogiri version 1.6.7.2 has been released, pulling in several upstream
patches to the vendored libxml2 to address the following CVE:

CVE-2015-7499
CVSS v2 Base Score: 5.0 (MEDIUM)

Heap-based buffer overflow in the xmlGROW function in parser.c
in libxml2 before 2.9.3 allows context-dependent attackers to
obtain sensitive process memory information via unspecified
vectors.

libxml2 could be made to crash if it opened a specially crafted
file. It was discovered that libxml2 incorrectly handled certain
malformed documents. If a user or automated system were tricked
into opening a specially crafted document, an attacker could
possibly cause libxml2 to crash, resulting in a denial of service.

Patched versions: [">= 1.6.7.2"]
Unaffected versions: ["< 1.6.0"]

Nokogiri gem contains several vulnerabilities in libxml2 and libxslt
Several vulnerabilities were discovered in the libxml2 and libxslt libraries
that the Nokogiri gem depends on.

CVE-2015-1819
A denial of service flaw was found in the way libxml2 parsed XML
documents. This flaw could cause an application that uses libxml2 to use an
excessive amount of memory.

CVE-2015-7941
libxml2 does not properly stop parsing invalid input, which allows
context-dependent attackers to cause a denial of service (out-of-bounds read
and libxml2 crash) via crafted specially XML data.

CVE-2015-7942
The xmlParseConditionalSections function in parser.c in libxml2
does not properly skip intermediary entities when it stops parsing invalid
input, which allows context-dependent attackers to cause a denial of service
(out-of-bounds read and crash) via crafted XML data.

CVE-2015-7995
The xsltStylePreCompute function in preproc.c in libxslt 1.1.28 does not
check whether the parent node is an element, which allows attackers to cause
a denial of service using a specially crafted XML document.

CVE-2015-8035
The xz_decomp function in xzlib.c in libxml2 2.9.1 does not
properly detect compression errors, which allows context-dependent attackers
to cause a denial of service (process hang) via crafted XML data.

Another vulnerability was discoverd in libxml2 that could cause parsing
of unclosed comments to result in "conditional jump or move depends on
uninitialized value(s)" and unsafe memory access. This issue does not have a
CVE assigned yet. See related URLs for details. Patched in v1.6.7.rc4.

Patched versions: ["~> 1.6.6.4", ">= 1.6.7.rc4"]
Unaffected versions: []

Changelog

Sourced from nokogiri's changelog.

1.6.8.1 / 2016-10-03

Dependency License Notes

Removes required dependency on the pkg-config gem. This dependency
was introduced in v1.6.8 and, because it's distributed under LGPL, was
objectionable to many Nokogiri users (#1488, #1496).

This version makes pkg-config an optional dependency. If it's
installed, it's used; but otherwise Nokogiri will attempt to work
around its absence.

1.6.8 / 2016-06-06

Security Notes

[MRI] Bundled libxml2 is upgraded to 2.9.4, which fixes many security issues. Many of these had previously been patched in the vendored libxml 2.9.2 in the 1.6.7.x branch, but some are newer.

See these libxml2 email posts for more:

• https://mail.gnome.org/archives/xml/2015-November/msg00012.html
• https://mail.gnome.org/archives/xml/2016-May/msg00023.html

For a more detailed analysis, you may care to read Canonical's take on these security issues:

• http://www.ubuntu.com/usn/usn-2994-1

[MRI] Bundled libxslt is upgraded to 1.1.29, which fixes a security issue as well as many long-known outstanding bugs, some features, some portability improvements, and general cleanup.

See this libxslt email post for more:

• https://mail.gnome.org/archives/xslt/2016-May/msg00004.html

Features

Several changes were made to improve performance:

• [MRI] Simplify NodeSet#to_a with a minor speed-up. (#1397)
• XML::Node#ancestors optimization. (#1297) (Thanks, Bruno Sutic!)
• Use Symbol#to_proc where we weren't previously. (#1296) (Thanks, Bruno Sutic!)
• XML::DTD#each uses implicit block calls. (Thanks, glaucocustodio!)
• Fall back to the pkg-config gem if we're having trouble finding the system libxml2. This should help many FreeBSD users. (#1417)
• Set document encoding appropriately even on blank document. (#1043) (Thanks, batter!)

Bug Fixes

... (truncated)

Commits

• 002e4d8 version bump to v1.6.8.1
• 3b9ee4b update CHANGELOG for pkg-config
• f2dd079 Make the pkg-config gem optional.
• 6b05c5a update v1.6.8 date in CHANGELOG
• 1103a64 version bump to v1.6.8 final
• 03d4022 update CHANGELOG with libxml2 USN info
• a7da0f9 make sure test_all will errexit
• 8d4ea86 make sure test_all doesn't require libxml-ruby
• 80e800b use eval_gemfile to load libxml-ruby
• 95ba49a test_all uses Bundler 1.12.*
• Additional commits viewable in compare view

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