Synopsis: Moderate: python security, bug fix, and enhancement update
Advisory ID: SLSA-2015:2101-1
Issue Date: 2015-11-19
CVE Numbers: CVE-2013-1753
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
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
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
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.
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.
* When importing the readline module from a Python script, Python no
longer produces erroneous random characters on stdout.
* The cProfile utility has been fixed to print all values that the “-s”
option supports when this option is used without a correct value.
* The load_cert_chain() function now accepts “None” as a keyfile argument.
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.
* Support for the ssl.PROTOCOL_TLSv1_2 protocol has been added to the ssl
* The ssl.SSLSocket.version() method is now available to access
information about the version of the SSL protocol used in a connection.
– Scientific Linux Development Team