Debian 9942 Published by

A python2.7 security update has been released for Debian GNU/Linux 8 and 9 Extended LTS to fix multiple vulnerabilities.

ELA-950-1 python2.7 security update

Package : python2.7
Version : 2.7.9-2-ds1-1+deb8u11 (jessie), 2.7.13-2+deb9u8 (stretch)

Related CVEs :

This update fixes multiple vulnerabilities concerning the urlparse module as
well as vulnerabilities concerning the heapq, hmac, plistlib and ssl

The `urlparse` module helps break Uniform Resource Locator (URL) strings
into components. The issue involves how the `urlparse` method does not
sanitize input and allows characters like `'\r'` and `'\n'` in the URL
path. This flaw allows an attacker to input a crafted URL, leading to
injection attacks.

A use-after-free exists in Python via `heappushpop` in `heapq`.

An XML External Entity (XXE) issue was discovered in Python. The
`plistlib` module no longer accepts entity declarations in XML plist files
to avoid XML vulnerabilities.

An issue was discovered in `compare_digest` in `Lib/` in Python.
Constant-time-defeating optimisations were possible in the accumulator
variable in `hmac.compare_digest`.

An issue in the `urlparse` component of Python allows attackers to bypass
blocklisting methods by supplying a URL that starts with blank characters.

The issue primarily affects servers written in Python (such as HTTP
servers) that use TLS client authentication. If a TLS server-side socket is
created, receives data into the socket buffer, and then is closed quickly,
there is a brief window where the `SSLSocket` instance will detect the
socket as "not connected" and won't initiate a handshake, but buffered data
will still be readable from the socket buffer. This data will not be
authenticated if the server-side TLS peer is expecting client certificate
authentication, and is indistinguishable from valid TLS stream data. Data
is limited in size to the amount that will fit in the buffer. (The TLS
connection cannot directly be used for data exfiltration because the
vulnerable code path requires that the connection be closed on
initialization of the `SSLSocket`.)

ELA-950-1 python2.7 security update