SB2021111066 - Red Hat Enterprise Linux 8 update for the python27:2.7 module



SB2021111066 - Red Hat Enterprise Linux 8 update for the python27:2.7 module

Published: November 10, 2021

Security Bulletin ID SB2021111066
CSH Severity
Medium
Patch available
YES
Number of vulnerabilities 8
Exploitation vector Remote access
Highest impact Code execution

Breakdown by Severity

Medium 63% Low 38%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 8 vulnerabilities.


1) Input validation error (CVE-ID: CVE-2021-23336)

CWE-ID: CWE-20 - Improper input validation

CVSSv4: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:U/U:Green


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

The vulnerability exists due to insufficient validation of user-supplied input in django.utils.http.limited_parse_qsl() when parsing strings with a semicolon (";"). A remote attacker can pass specially crafted data to the application and perform a spoofing attack.


2) Infinite loop (CVE-ID: CVE-2021-20270)

CWE-ID: CWE-835 - Loop with Unreachable Exit Condition ('Infinite Loop')

CVSSv4: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:U/U:Clear


The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to infinite loop. A remote attacker can consume all available system resources and cause denial of service conditions.


3) Path traversal (CVE-ID: CVE-2021-20095)

CWE-ID: CWE-22 - Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')

CVSSv4: CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:U/U:Clear


The vulnerability allows a local user to perform directory traversal attacks.

The vulnerability exists due to input validation error when processing directory traversal sequences. A local user can load arbitrary files on disk and execute arbitrary code.


4) Resource management error (CVE-ID: CVE-2021-27291)

CWE-ID: CWE-399 - Resource Management Errors

CVSSv4: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green


The vulnerability allows a remote attacker to perform a denial of service (ReDoS) attack.

The vulnerability exists due to improper management of internal resources within the application. A remote attacker can pass specially crafted data to the application and perform regular expression denial of service (ReDoS) attack.


5) Incorrect Regular Expression (CVE-ID: CVE-2020-28493)

CWE-ID: CWE-185 - Incorrect Regular Expression

CVSSv4: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green


The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to incorrect subpattern applied to untrusted input. A remote attacker can pass specially crafted data to the application and perform a regular expression DoS (ReDOS) attack.


6) Code Injection (CVE-ID: CVE-2020-27619)

CWE-ID: CWE-94 - Improper Control of Generation of Code ('Code Injection')

CVSSv4: CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Green


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

The vulnerability exists due to Python executed eval() function on the code, retrieved via HTTP protocol in Lib/test/multibytecodec_support.py CJK codec tests. A remote attacker with ability to intercept network traffic can perform a Man-in-the-Middle (MitM) attack and execute arbitrary Python code on the system.


7) Path traversal (CVE-ID: CVE-2021-42771)

CWE-ID: CWE-22 - Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')

CVSSv4: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:U/U:Green


The vulnerability allows a remote attacker to user compromise the affected system.

The vulnerability exists due to input validation error when processing directory traversal sequences within the locale .dat files in Babel.Locale. A remote user can load a malicious .dat file containing serialized Python objects and execute arbitrary code on the system.


8) Cross-site scripting (CVE-ID: CVE-2021-28957)

CWE-ID: CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

CVSSv4: CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N/E:U/U:Clear


The disclosed vulnerability allows a remote attacker to perform cross-site scripting (XSS) attacks.

The vulnerability exists due to insufficient sanitization of user-supplied data. When disabling the safe_attrs_only and forms arguments, the Cleaner class does not remove the formaction attribute allowing for JS to bypass the sanitizer. A remote attacker can trick the victim to follow a specially crafted link and execute arbitrary HTML and script code in user's browser in context of vulnerable website.

Successful exploitation of this vulnerability may allow a remote attacker to steal potentially sensitive information, change appearance of the web page, perform phishing and drive-by-download attacks.


Remediation

Install update from vendor's website.