Debian DLA-2337-1 : python2.7 security update

critical Nessus Plugin ID 139757
New! Plugin Severity Now Using CVSS v3

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Synopsis

The remote Debian host is missing a security update.

Description

Multiple vulnerabilities were discovered in Python2.7, an interactive high-level object-oriented language.

CVE-2018-20852

By using a malicious server an attacker might steal cookies that are meant for other domains.

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.

CVE-2019-16056

The email module wrongly parses email addresses that contain multiple @ characters. An application that uses the email module and implements some kind of checks on the From/To headers of a message could be tricked into accepting an email address that should be denied.

CVE-2019-20907

Opening a crafted tar file could result in an infinite loop due to missing header validation.

For Debian 9 stretch, these problems have been fixed in version 2.7.13-2+deb9u4.

We recommend that you upgrade your python2.7 packages.

For the detailed security status of python2.7 please refer to its security tracker page at:
https://security-tracker.debian.org/tracker/python2.7

NOTE: Tenable Network Security has extracted the preceding description block directly from the DLA security advisory. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.

Solution

Upgrade the affected packages.

See Also

https://lists.debian.org/debian-lts-announce/2020/08/msg00034.html

https://packages.debian.org/source/stretch/python2.7

https://security-tracker.debian.org/tracker/source-package/python2.7

Plugin Details

Severity: Critical

ID: 139757

File Name: debian_DLA-2337.nasl

Version: 1.4

Type: local

Agent: unix

Published: 8/24/2020

Updated: 2/19/2021

Dependencies: ssh_get_info.nasl

Risk Information

CVSS Score Source: CVE-2019-9948

VPR

Risk Factor: High

Score: 8.4

CVSS v2

Risk Factor: Medium

Base Score: 6.4

Temporal Score: 4.7

Vector: AV:N/AC:L/Au:N/C:P/I:P/A:N

Temporal Vector: E:U/RL:OF/RC:C

CVSS v3

Risk Factor: Critical

Base Score: 9.1

Temporal Score: 7.9

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

Temporal Vector: E:U/RL:O/RC:C

Vulnerability Information

CPE: p-cpe:/a:debian:debian_linux:idle-python2.7, p-cpe:/a:debian:debian_linux:libpython2.7, p-cpe:/a:debian:debian_linux:libpython2.7-dbg, p-cpe:/a:debian:debian_linux:libpython2.7-dev, p-cpe:/a:debian:debian_linux:libpython2.7-minimal, p-cpe:/a:debian:debian_linux:libpython2.7-stdlib, p-cpe:/a:debian:debian_linux:libpython2.7-testsuite, p-cpe:/a:debian:debian_linux:python2.7, p-cpe:/a:debian:debian_linux:python2.7-dbg, p-cpe:/a:debian:debian_linux:python2.7-dev, p-cpe:/a:debian:debian_linux:python2.7-doc, p-cpe:/a:debian:debian_linux:python2.7-examples, p-cpe:/a:debian:debian_linux:python2.7-minimal, cpe:/o:debian:debian_linux:9.0

Required KB Items: Host/local_checks_enabled, Host/Debian/release, Host/Debian/dpkg-l

Exploit Ease: No known exploits are available

Patch Publication Date: 8/22/2020

Vulnerability Publication Date: 3/8/2019

Reference Information

CVE: CVE-2018-20852, CVE-2019-10160, CVE-2019-16056, CVE-2019-20907, CVE-2019-5010, CVE-2019-9636, CVE-2019-9740, CVE-2019-9947, CVE-2019-9948

IAVA: 2020-A-0340-S