SB2019110530 - Red Hat Enterprise Linux 8 update for the python27:2.7 module

Security Bulletin ID SB2019110530

Severity

High

Patch available

YES

Number of vulnerabilities 6

Exploitation vector Remote access

Highest impact Code execution

Breakdown by Severity

Low
Medium
High
Critical

Description

This security bulletin contains information about 6 secuirty vulnerabilities.

1) Command injection (CVE-ID: CVE-2019-6446)

The vulnerability allows a remote attacker to execute arbitrary commands on the target system.

The vulnerability exists due to the unsafe use of the pickle Python module. A remote attacker can trick the victim into loading malicious content with the affected application on a targeted system by using misleading language and instructions that allows to execute arbitrary code with elevated privileges.

Successful exploitation of this vulnerability may result in complete compromise of vulnerable system.

2) 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.

3) 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.

4) 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')

5) CRLF injection (CVE-ID: CVE-2019-11236)

The vulnerability allows a remote attacker to perform a spoofing attack.

The vulnerability exists due to insufficient filtration of user-supplied data passed via HTTP request parameters to urllib3 library. A remote attacker can pass specially crafted data that contains CRLF sequences and perform a spoofing attack.

6) Improper Certificate Validation (CVE-ID: CVE-2019-11324)

The vulnerability allows a remote attacker to compromise the target system.

The vulnerability exists due to the urllib3 library for Python mishandles certain cases where the desired set of CA certificates is different from the OS store of CA certificates. A remote attacker can cause the certificates to be considered trusted contrary to expectations. This is related to use of the "ssl_context", "ca_certs" or "ca_certs_dir" argument.

Remediation

Install update from vendor's website.

References

https://access.redhat.com/errata/RHSA-2019:3335