7.5 - RHSA-2011:0027

Problem Description:

Updated python packages that fix multiple security issues, several bugs, and add two enhancements are now available for Red Hat Enterprise Linux 5.

The Red Hat Security Response Team has rated this update as having low 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.

2. Relevant releases/architectures:

RHEL Desktop Workstation (v. 5 client) - i386, x86_64 Red Hat Enterprise Linux (v. 5 server) - i386, ia64, ppc, s390x, x86_64 Red Hat Enterprise Linux Desktop (v. 5 client) - i386, x86_64

3. Description:

Python is an interpreted, interactive, object-oriented programming language.

It was found that many applications embedding the Python interpreter did not specify a valid full path to the script or application when calling the PySys_SetArgv API function, which could result in the addition of the current working directory to the module search path (sys.path). A local attacker able to trick a victim into running such an application in an attacker-controlled directory could use this flaw to execute code with the victim's privileges. This update adds the PySys_SetArgvEx API. Developers can modify their applications to use this new API, which sets sys.argv without modifying sys.path. (CVE-2008-5983)

Multiple flaws were found in the Python rgbimg module. If an application written in Python was using the rgbimg module and loaded a specially-crafted SGI image file, it could cause the application to crash or, possibly, execute arbitrary code with the privileges of the user running the application. (CVE-2009-4134, CVE-2010-1449, CVE-2010-1450)

Multiple flaws were found in the Python audioop module. Supplying certain inputs could cause the audioop module to crash or, possibly, execute arbitrary code. (CVE-2010-1634, CVE-2010-2089)

This update also fixes the following bugs:

* When starting a child process from the subprocess module in Python 2.4, the parent process could leak file descriptors if an error occurred. This update resolves the issue. (BZ#609017)

* Prior to Python 2.7, programs that used "ulimit -n" to enable communication with large numbers of subprocesses could still monitor only 1024 file descriptors at a time, which caused an exception:

ValueError: filedescriptor out of range in select()

This was due to the subprocess module using the "select" system call. The module now uses the "poll" system call, removing this limitation. (BZ#609020)

* Prior to Python 2.5, the tarfile module failed to unpack tar files if the path was longer than 100 characters. This update backports the tarfile module from Python 2.5 and the issue no longer occurs. (BZ#263401)

* The email module incorrectly implemented the logic for obtaining attachment file names: the get_filename() fallback for using the deprecated "name" parameter of the "Content-Type" header erroneously used the "Content-Disposition" header. This update backports a fix from Python 2.6, which resolves this issue. (BZ#644147)

* Prior to version 2.5, Python's optimized memory allocator never released memory back to the system. The memory usage of a long-running Python process would resemble a "high-water mark". This update backports a fix from Python 2.5a1, which frees unused arenas, and adds a non-standard sys._debugmallocstats() function, which prints diagnostic information to stderr. Finally, when running under Valgrind, the optimized allocator is deactivated, to allow more convenient debugging of Python memory usage issues. (BZ#569093)

* The urllib and urllib2 modules ignored the no_proxy variable, which could lead to programs such as "yum" erroneously accessing a proxy server for URLs covered by a "no_proxy" exclusion. This update backports fixes of urllib and urllib2, which respect the "no_proxy" variable, which fixes these issues. (BZ#549372)

As well, this update adds the following enhancements:

* This update introduces a new python-libs package, subsuming the majority of the content of the core python package. This makes both 32-bit and 64-bit Python libraries available on PowerPC systems. (BZ#625372)

* The python-libs.i386 package is now available for 64-bit Itanium with the 32-bit Itanium compatibility mode. (BZ#644761)

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

4. Solution:

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

This update is available via the Red Hat Network. Details on how to use the Red Hat Network to apply this update are available at http://kbase.redhat.com/faq/docs/DOC-11259

5. Bugs fixed (http://bugzilla.redhat.com/):

482814 - CVE-2008-5983 python: untrusted python modules search path 541698 - CVE-2009-4134 CVE-2010-1449 CVE-2010-1450 python: rgbimg: multiple security issues 569093 - Python 2.4's arena allocator does not release memory back to the system, leading to "high-water mark" memory usage 590690 - CVE-2010-1634 python: audioop: incorrect integer overflow checks 598197 - CVE-2010-2089 Python: Memory corruption in audioop module 609017 - subprocess leaves open fds on construction error 609020 - subprocess fails in select when descriptors are large 625372 - split python-libs subpackage 644147 - Patch for get_filename in email.message when content-disposition is missing 644761 - python-libs conflict on ia64 compatlayer