SB2020040167 - Red Hat Enterprise Linux 7 update for python



SB2020040167 - Red Hat Enterprise Linux 7 update for python

Published: April 1, 2020

Security Bulletin ID SB2020040167
Severity
Medium
Patch available
YES
Number of vulnerabilities 6
Exploitation vector Remote access
Highest impact Denial of service

Breakdown by Severity

Medium 83% Low 17%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 6 secuirty vulnerabilities.


1) Improper input validation (CVE-ID: CVE-2018-1060)

The vulnerability allows a remote attacker to cause DoS condition on he target system.

The weakness exists due to the way catastrophic backtracking was implemented in apop() method in pop3lib. A remote attacker can cause the service to crash.

2) Improper input validation (CVE-ID: CVE-2018-1061)

The vulnerability allows a remote attacker to cause DoS condition on he target system.

The weakness exists due to the way catastrophic backtracking was implemented in python's difflib.IS_LINE_JUNK method difflib. A remote attacker can cause the service to crash.

3) XXE attack (CVE-ID: CVE-2018-14647)

The vulnerability allows a remote attacker to conduct XXE-attack.

The vulnerability exists due to improper handling of XML External Entities (XXEs) when parsing an XML file. A remote attacker can trick the victim into open an XML file that submits malicious input, trigger pathological hash collisions in Expat's internal data structures, consume large amounts CPU and RAM, and cause a denial of service (DoS) condition.


4) CRLF injection (CVE-ID: CVE-2019-9740)

The vulnerability allows a remote attacker to perform CRLF injection attacks.

The vulnerability exists within urllib2 implementation for Python 2.x and urllib3 implementation for Python 3.x when processing the path component of a URL after the "?" character within the urllib.request.urlopen() call. A remote attacker with ability to control URL, passed to the application, can use CRLF sequences to split the HTTP request and inject arbitrary HTTP headers into request, made by the application.


5) CRLF injection (CVE-ID: CVE-2019-9947)

The vulnerability allows a remote attacker to perform CRLF injection attacks.

The vulnerability exists within urllib2 implementation for Python 2.x and urllib3 implementation for Python 3.x when processing the path component of a URL that lacks the "?" character within the urllib.request.urlopen() call. A remote attacker with ability to control URL, passed to the application, can use CRLF sequences to split the HTTP request and inject arbitrary HTTP headers into request, made by the application.


6) Exposed dangerous method or function (CVE-ID: CVE-2019-9948)

The vulnerability allows a remote attacker to bypass certain security restrictions.

The vulnerability exists due to urllib implementation in Python 2.x supports the local_file: scheme. An attacker with ability to control input data, such as URL, can bypass protection mechanisms that blacklist file: URIs and view contents of arbitrary file on the system.

PoC:

urllib.urlopen('local_file:///etc/passwd')

Remediation

Install update from vendor's website.