Synopsis

Moderate: python security, bug fix, and enhancement update

Type/Severity

Security Advisory: Moderate

Topic

Updated python packages that fix multiple security issues, several bugs,
and add various enhancements are now available for Red Hat Enterprise
Linux 7.

Red Hat Product Security has rated this update as having Moderate security
impact. Common Vulnerability Scoring System (CVSS) base scores, which give
detailed severity ratings, are available for each vulnerability from the
CVE links in the References section.

Description

Python is an interpreted, interactive, object-oriented programming language
often compared to Tcl, Perl, Scheme, or Java. Python includes modules,
classes, exceptions, very high level dynamic data types and dynamic typing.
Python supports interfaces to many system calls and libraries, as well as
to various windowing systems (X11, Motif, Tk, Mac and MFC).

It was discovered that the Python xmlrpclib module did not restrict the
size of gzip-compressed HTTP responses. A malicious XMLRPC server could
cause an XMLRPC client using xmlrpclib to consume an excessive amount of
memory. (CVE-2013-1753)

It was discovered that multiple Python standard library modules
implementing network protocols (such as httplib or smtplib) failed to
restrict the sizes of server responses. A malicious server could cause a
client using one of the affected modules to consume an excessive amount of
memory. (CVE-2013-1752)

It was discovered that the CGIHTTPServer module incorrectly handled URL
encoded paths. A remote attacker could use this flaw to execute scripts
outside of the cgi-bin directory, or disclose the source code of the
scripts in the cgi-bin directory. (CVE-2014-4650)

An integer overflow flaw was found in the way the buffer() function handled
its offset and size arguments. An attacker able to control these arguments
could use this flaw to disclose portions of the application memory or cause
it to crash. (CVE-2014-7185)

A flaw was found in the way the json module handled negative index
arguments passed to certain functions (such as raw_decode()). An attacker
able to control the index value passed to one of the affected functions
could possibly use this flaw to disclose portions of the application
memory. (CVE-2014-4616)

The Python standard library HTTP client modules (such as httplib or urllib)
did not perform verification of TLS/SSL certificates when connecting to
HTTPS servers. A man-in-the-middle attacker could use this flaw to hijack
connections and eavesdrop or modify transferred data. (CVE-2014-9365)

Note: The Python standard library was updated to make it possible to enable
certificate verification by default. However, for backwards compatibility,
verification remains disabled by default. Future updates may change this
default. Refer to the Knowledgebase article 2039753 linked to in the
References section for further details about this change. (BZ#1219108)

This update also fixes the following bugs:

• Subprocesses used with the Eventlet library or regular threads previously

tried to close epoll file descriptors twice, which led to an "Invalid
argument" error. Subprocesses have been fixed to close the file descriptors
only once. (BZ#1103452)

• When importing the readline module from a Python script, Python no longer

produces erroneous random characters on stdout. (BZ#1189301)

• The cProfile utility has been fixed to print all values that the "-s"

option supports when this option is used without a correct value.
(BZ#1237107)

• The load_cert_chain() function now accepts "None" as a keyfile argument.

(BZ#1250611)

In addition, this update adds the following enhancements:

• Security enhancements as described in PEP 466 have been backported to the

Python standard library, for example, new features of the ssl module:
Server Name Indication (SNI) support, support for new TLSv1.x protocols,
new hash algorithms in the hashlib module, and many more. (BZ#1111461)

• Support for the ssl.PROTOCOL_TLSv1_2 protocol has been added to the ssl

library. (BZ#1192015)

• The ssl.SSLSocket.version() method is now available to access information

about the version of the SSL protocol used in a connection. (BZ#1259421)

All python users are advised to upgrade to these updated packages, which
contain backported patches to correct these issues and add these
enhancements.

Solution

Before applying this update, make sure all previously released errata
relevant to your system have been applied.

For details on how to apply this update, refer to:

https://access.redhat.com/articles/11258

Affected Products

• Red Hat Enterprise Linux Server 7 x86_64
• Red Hat Enterprise Linux for x86_64 - Extended Update Support 7.7 x86_64
• Red Hat Enterprise Linux for x86_64 - Extended Update Support 7.6 x86_64
• Red Hat Enterprise Linux for x86_64 - Extended Update Support 7.5 x86_64
• Red Hat Enterprise Linux for x86_64 - Extended Update Support 7.4 x86_64
• Red Hat Enterprise Linux for x86_64 - Extended Update Support 7.3 x86_64
• Red Hat Enterprise Linux Server - AUS 7.7 x86_64
• Red Hat Enterprise Linux Server - AUS 7.6 x86_64
• Red Hat Enterprise Linux Server - AUS 7.4 x86_64
• Red Hat Enterprise Linux Workstation 7 x86_64
• Red Hat Enterprise Linux Desktop 7 x86_64
• Red Hat Enterprise Linux for IBM z Systems 7 s390x
• Red Hat Enterprise Linux for IBM z Systems - Extended Update Support 7.7 s390x
• Red Hat Enterprise Linux for IBM z Systems - Extended Update Support 7.6 s390x
• Red Hat Enterprise Linux for IBM z Systems - Extended Update Support 7.5 s390x
• Red Hat Enterprise Linux for IBM z Systems - Extended Update Support 7.4 s390x
• Red Hat Enterprise Linux for IBM z Systems - Extended Update Support 7.3 s390x
• Red Hat Enterprise Linux for Power, big endian 7 ppc64
• Red Hat Enterprise Linux for Power, big endian - Extended Update Support 7.7 ppc64
• Red Hat Enterprise Linux for Power, big endian - Extended Update Support 7.6 ppc64
• Red Hat Enterprise Linux for Power, big endian - Extended Update Support 7.5 ppc64
• Red Hat Enterprise Linux for Power, big endian - Extended Update Support 7.4 ppc64
• Red Hat Enterprise Linux for Power, big endian - Extended Update Support 7.3 ppc64
• Red Hat Enterprise Linux for Scientific Computing 7 x86_64
• Red Hat Enterprise Linux Server from RHUI 7 x86_64
• Red Hat Enterprise Linux EUS Compute Node 7.7 x86_64
• Red Hat Enterprise Linux EUS Compute Node 7.6 x86_64
• Red Hat Enterprise Linux EUS Compute Node 7.5 x86_64
• Red Hat Enterprise Linux EUS Compute Node 7.4 x86_64
• Red Hat Enterprise Linux EUS Compute Node 7.3 x86_64
• Red Hat Enterprise Linux Server - AUS 7.3 x86_64
• Red Hat Enterprise Linux for Power, little endian 7 ppc64le
• Red Hat Enterprise Linux for Power, little endian - Extended Update Support 7.7 ppc64le
• Red Hat Enterprise Linux for Power, little endian - Extended Update Support 7.6 ppc64le
• Red Hat Enterprise Linux for Power, little endian - Extended Update Support 7.5 ppc64le
• Red Hat Enterprise Linux for Power, little endian - Extended Update Support 7.4 ppc64le
• Red Hat Enterprise Linux for Power, little endian - Extended Update Support 7.3 ppc64le
• Red Hat Enterprise Linux for Power, little endian - Extended Update Support 7.2 ppc64le
• Red Hat Enterprise Linux Server - TUS 7.7 x86_64
• Red Hat Enterprise Linux Server - TUS 7.6 x86_64
• Red Hat Enterprise Linux Server - TUS 7.3 x86_64
• Red Hat Enterprise Linux Server (for IBM Power LE) - Update Services for SAP Solutions 7.7 ppc64le
• Red Hat Enterprise Linux Server (for IBM Power LE) - Update Services for SAP Solutions 7.6 ppc64le
• Red Hat Enterprise Linux Server (for IBM Power LE) - Update Services for SAP Solutions 7.4 ppc64le
• Red Hat Enterprise Linux Server (for IBM Power LE) - Update Services for SAP Solutions 7.3 ppc64le
• Red Hat Enterprise Linux Server - Update Services for SAP Solutions 7.7 x86_64
• Red Hat Enterprise Linux Server - Update Services for SAP Solutions 7.6 x86_64
• Red Hat Enterprise Linux Server - Update Services for SAP Solutions 7.4 x86_64
• Red Hat Enterprise Linux Server - Update Services for SAP Solutions 7.3 x86_64

Fixes

• BZ - 1046170 - CVE-2013-1753 python: XMLRPC library unrestricted decompression of HTTP responses using gzip enconding
• BZ - 1046174 - CVE-2013-1752 python: multiple unbound readline() DoS flaws in python stdlib
• BZ - 1058482 - tmpwatch removes python multiprocessing sockets
• BZ - 1112285 - CVE-2014-4616 python: missing boundary check in JSON module
• BZ - 1113527 - CVE-2014-4650 python: CGIHTTPServer module does not properly handle URL-encoded path separators in URLs
• BZ - 1146026 - CVE-2014-7185 python: buffer() integer overflow leading to out of bounds read
• BZ - 1173041 - CVE-2014-9365 python: failure to validate certificates in the HTTP client with TLS (PEP 476)
• BZ - 1177613 - setup.py bdist_rpm NameError: global name 'get_python_version' is not defined
• BZ - 1181624 - multiprocessing BaseManager serve_client() does not check EINTR on recv
• BZ - 1237107 - cProfile main() traceback if options syntax is invalid
• BZ - 1250611 - SSLContext.load_cert_chain() keyfile argument can't be set to None
• BZ - 1259421 - Backport SSLSocket.version() to python 2.7.5

CVEs

• CVE-2013-1752
• CVE-2013-1753
• CVE-2014-4616
• CVE-2014-4650
• CVE-2014-7185

References