Debian Long Term Support / LTS Security Information / 2019 / Security Information -- DLA-1834-1 python2.7

Debian Security Advisory

DLA-1834-1 python2.7 -- LTS security update

Date Reported:

24 Jun 2019

Affected Packages:

python2.7

Vulnerable:

Yes

Security database references:

In the Debian bugtracking system: Bug 921039, Bug 921040, Bug 924073.
In Mitre's CVE dictionary: CVE-2018-14647, CVE-2019-5010, CVE-2019-9636, CVE-2019-9740, CVE-2019-9947, CVE-2019-9948, CVE-2019-10160.

More information:

Multiple vulnerabilities were discovered in Python, an interactive high-level object-oriented language, including

• CVE-2018-14647

  Python's elementtree C accelerator failed to initialise Expat's hash salt during initialization. This could make it easy to conduct denial of service attacks against Expat by constructing an XML document that would cause pathological hash collisions in Expat's internal data structures, consuming large amounts CPU and RAM.

• CVE-2019-5010

  NULL pointer dereference using a specially crafted X509 certificate.

• CVE-2019-9636

  Improper Handling of Unicode Encoding (with an incorrect netloc) during NFKC normalization resulting in information disclosure (credentials, cookies, etc. that are cached against a given hostname). A specially crafted URL could be incorrectly parsed to locate cookies or authentication data and send that information to a different host than when parsed correctly.

• CVE-2019-9740

  An issue was discovered in urllib2 where CRLF injection is possible if the attacker controls a url parameter, as demonstrated by the first argument to urllib.request.urlopen with \r\n (specifically in the query string after a ? character) followed by an HTTP header or a Redis command.

• CVE-2019-9947

  An issue was discovered in urllib2 where CRLF injection is possible if the attacker controls a url parameter, as demonstrated by the first argument to urllib.request.urlopen with \r\n (specifically in the path component of a URL that lacks a ? character) followed by an HTTP header or a Redis command. This is similar to the CVE-2019-9740 query string issue.

• CVE-2019-9948

  urllib supports the local_file: scheme, which makes it easier for remote attackers to bypass protection mechanisms that blacklist file: URIs, as demonstrated by triggering a urllib.urlopen('local_file:///etc/passwd') call.

• CVE-2019-10160

  A security regression of CVE-2019-9636 was discovered which still allows an attacker to exploit CVE-2019-9636 by abusing the user and password parts of a URL. When an application parses user-supplied URLs to store cookies, authentication credentials, or other kind of information, it is possible for an attacker to provide specially crafted URLs to make the application locate host-related information (e.g. cookies, authentication data) and send them to a different host than where it should, unlike if the URLs had been correctly parsed. The result of an attack may vary based on the application.

For Debian 8 Jessie, these problems have been fixed in version 2.7.9-2+deb8u3.

We recommend that you upgrade your python2.7 packages.

Further information about Debian LTS security advisories, how to apply these updates to your system and frequently asked questions can be found at: https://wiki.debian.org/LTS