RHEL 7 : rh-python38 (RHSA-2021:3254)

high Nessus Plugin ID 152781

Synopsis

The remote Red Hat host is missing one or more security updates.

Description

The remote Redhat Enterprise Linux 7 host has packages installed that are affected by multiple vulnerabilities as referenced in the RHSA-2021:3254 advisory.

Python is an interpreted, interactive, object-oriented programming language, which includes modules, classes, exceptions, very high level dynamic data types and dynamic typing. Python supports interfaces to many system calls and libraries, as well as to various windowing systems.

The following packages have been upgraded to a later upstream version: rh-python38-python (3.8.11).
(BZ#1969523)

Security Fix(es):

* python-cryptography: Bleichenbacher timing oracle attack against RSA decryption (CVE-2020-25659)

* python: Unsafe use of eval() on data retrieved via HTTP in the test suite (CVE-2020-27619)

* python-lxml: mXSS due to the use of improper parser (CVE-2020-27783)

* python-jinja2: ReDoS vulnerability due to the sub-pattern (CVE-2020-28493)

* python-cryptography: Large inputs for symmetric encryption can trigger integer overflow leading to buffer overflow (CVE-2020-36242)

* python: Stack-based buffer overflow in PyCArg_repr in _ctypes/callproc.c (CVE-2021-3177)

* python: Information disclosure via pydoc (CVE-2021-3426)

* python-babel: Relative path traversal allows attacker to load arbitrary locale files and execute arbitrary code (CVE-2021-20095)

* python: Web cache poisoning via urllib.parse.parse_qsl and urllib.parse.parse_qs by using a semicolon in query parameters (CVE-2021-23336)

* python-lxml: Missing input sanitization for formaction HTML5 attributes may lead to XSS (CVE-2021-28957)

* python-ipaddress: Improper input validation of octal strings (CVE-2021-29921)

* python-urllib3: ReDoS in the parsing of authority part of URL (CVE-2021-33503)

* python-pip: Incorrect handling of unicode separators in git references (CVE-2021-3572)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

Additional information

* Changes in the default separator for the Python urllib parsing functions

To mitigate the Web Cache Poisoning CVE-2021-23336 in the Python urllib library, the default separator for the urllib.parse.parse_qsl and urllib.parse.parse_qs functions is being changed from both ampersand (&) and semicolon (;) to only an ampersand.

The change of the default separator is potentially backwards incompatible, therefore Red Hat provides a way to configure the behavior in Python packages where the default separator has been changed. In addition, the affected urllib parsing functions issue a warning if they detect that a customers application has been affected by the change.

For more information, see the Knowledgebase article Mitigation of Web Cache Poisoning in the Python urllib library (CVE-2021-23336) linked from the References section.

* The Python ipaddress module no longer allows leading zeros in IPv4 addresses

To mitigate CVE-2021-29921, the Python ipaddress module now rejects IPv4 addresses with leading zeros with an AddressValueError: Leading zeros are not permitted error.

Customers who rely on the previous behavior can pre-process their IPv4 address inputs to strip the leading zeros off. For details, see the Red Hat Software Collections 3.7 Release Notes.

Tenable has extracted the preceding description block directly from the Red Hat Enterprise Linux security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

Solution

Update the affected packages.

See Also

http://www.nessus.org/u?431dd8f1

http://www.nessus.org/u?814bf75b

https://access.redhat.com/articles/5860431

https://access.redhat.com/errata/RHSA-2021:3254

https://bugzilla.redhat.com/show_bug.cgi?id=1889886

https://bugzilla.redhat.com/show_bug.cgi?id=1889988

https://bugzilla.redhat.com/show_bug.cgi?id=1901633

https://bugzilla.redhat.com/show_bug.cgi?id=1918168

https://bugzilla.redhat.com/show_bug.cgi?id=1926226

https://bugzilla.redhat.com/show_bug.cgi?id=1928707

https://bugzilla.redhat.com/show_bug.cgi?id=1928904

https://bugzilla.redhat.com/show_bug.cgi?id=1935913

https://bugzilla.redhat.com/show_bug.cgi?id=1941534

https://bugzilla.redhat.com/show_bug.cgi?id=1955615

https://bugzilla.redhat.com/show_bug.cgi?id=1957458

https://bugzilla.redhat.com/show_bug.cgi?id=1962856

https://bugzilla.redhat.com/show_bug.cgi?id=1968074

https://bugzilla.redhat.com/show_bug.cgi?id=1969523

https://access.redhat.com/security/updates/classification/#moderate

Plugin Details

Severity: High

ID: 152781

File Name: redhat-RHSA-2021-3254.nasl

Version: 1.13

Type: local

Agent: unix

Published: 8/24/2021

Updated: 9/10/2025

Supported Sensors: Frictionless Assessment AWS, Frictionless Assessment Azure, Frictionless Assessment Agent, Nessus Agent, Agentless Assessment, Continuous Assessment, Nessus

Risk Information

VPR

Risk Factor: Medium

Score: 6.7

Vendor

Vendor Severity: Moderate

CVSS v2

Risk Factor: High

Base Score: 7.5

Temporal Score: 5.9

Vector: CVSS2#AV:N/AC:L/Au:N/C:P/I:P/A:P

CVSS Score Source: CVE-2021-3177

CVSS v3

Risk Factor: Critical

Base Score: 9.8

Temporal Score: 8.8

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

Temporal Vector: CVSS:3.0/E:P/RL:O/RC:C

CVSS v4

Risk Factor: High

Base Score: 8.8

Threat Score: 7.8

Threat Vector: CVSS:4.0/E:P

Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:H/SC:N/SI:N/SA:N

CVSS Score Source: CVE-2020-36242

Vulnerability Information

CPE: p-cpe:/a:redhat:enterprise_linux:rh-python38-python-idle, p-cpe:/a:redhat:enterprise_linux:rh-python38-python-devel, p-cpe:/a:redhat:enterprise_linux:rh-python38-python-debug, p-cpe:/a:redhat:enterprise_linux:rh-python38-python-rpm-macros, p-cpe:/a:redhat:enterprise_linux:rh-python38-python-srpm-macros, p-cpe:/a:redhat:enterprise_linux:rh-python38-python-jinja2, p-cpe:/a:redhat:enterprise_linux:rh-python38-python-babel, p-cpe:/a:redhat:enterprise_linux:rh-python38-python-urllib3, p-cpe:/a:redhat:enterprise_linux:rh-python38-python-pip-wheel, cpe:/o:redhat:enterprise_linux:7, p-cpe:/a:redhat:enterprise_linux:rh-python38-python-test, p-cpe:/a:redhat:enterprise_linux:rh-python38-babel, p-cpe:/a:redhat:enterprise_linux:rh-python38-python-tkinter, p-cpe:/a:redhat:enterprise_linux:rh-python38-python-lxml, p-cpe:/a:redhat:enterprise_linux:rh-python38-python-cryptography, p-cpe:/a:redhat:enterprise_linux:rh-python38-python-libs, p-cpe:/a:redhat:enterprise_linux:rh-python38-python, p-cpe:/a:redhat:enterprise_linux:rh-python38-python-pip

Required KB Items: Host/local_checks_enabled, Host/RedHat/release, Host/RedHat/rpm-list, Host/cpu

Exploit Available: true

Exploit Ease: Exploits are available

Patch Publication Date: 8/24/2021

Vulnerability Publication Date: 10/22/2020

Reference Information

CVE: CVE-2020-25659, CVE-2020-27619, CVE-2020-27783, CVE-2020-28493, CVE-2020-36242, CVE-2021-23336, CVE-2021-28957, CVE-2021-29921, CVE-2021-3177, CVE-2021-33503, CVE-2021-3426, CVE-2021-3572, CVE-2021-3733, CVE-2021-4189, CVE-2021-42771, CVE-2022-0391

CWE: 119, 120, 20, 200, 22, 252, 385, 400, 444, 74, 79, 835, 95

IAVA: 2021-A-0052-S, 2021-A-0263-S

RHSA: 2021:3254