CVE-2021-3733
Severity CVSS v4.0:
Pending analysis
Type:
CWE-400
Uncontrolled Resource Consumption ('Resource Exhaustion')
Publication date:
10/03/2022
Last modified:
03/11/2025
Description
There's a flaw in urllib's AbstractBasicAuthHandler class. An attacker who controls a malicious HTTP server that an HTTP client (such as web browser) connects to, could trigger a Regular Expression Denial of Service (ReDOS) during an authentication request with a specially crafted payload that is sent by the server to the client. The greatest threat that this flaw poses is to application availability.
Impact
Base Score 3.x
6.50
Severity 3.x
MEDIUM
Base Score 2.0
4.00
Severity 2.0
MEDIUM
Vulnerable products and versions
| CPE | From | Up to |
|---|---|---|
| cpe:2.3:a:python:python:*:*:*:*:*:*:*:* | 3.6.14 (excluding) | |
| cpe:2.3:a:python:python:*:*:*:*:*:*:*:* | 3.7.0 (including) | 3.7.11 (excluding) |
| cpe:2.3:a:python:python:*:*:*:*:*:*:*:* | 3.8.0 (including) | 3.8.10 (excluding) |
| cpe:2.3:a:python:python:*:*:*:*:*:*:*:* | 3.9.0 (including) | 3.9.5 (excluding) |
| cpe:2.3:a:python:python:3.10.0:-:*:*:*:*:*:* | ||
| cpe:2.3:a:redhat:codeready_linux_builder:8.0:*:*:*:*:*:*:* | ||
| cpe:2.3:a:redhat:codeready_linux_builder_for_ibm_z_systems:8.0:*:*:*:*:*:*:* | ||
| cpe:2.3:a:redhat:codeready_linux_builder_for_power_little_endian:8.0:*:*:*:*:*:*:* | ||
| cpe:2.3:o:redhat:enterprise_linux:8.0:*:*:*:*:*:*:* | ||
| cpe:2.3:o:redhat:enterprise_linux_eus:8.4:*:*:*:*:*:*:* | ||
| cpe:2.3:o:redhat:enterprise_linux_for_ibm_z_systems:8.0:*:*:*:*:*:*:* | ||
| cpe:2.3:o:redhat:enterprise_linux_for_ibm_z_systems_eus:8.4:*:*:*:*:*:*:* | ||
| cpe:2.3:o:redhat:enterprise_linux_for_power_little_endian:8.0:*:*:*:*:*:*:* | ||
| cpe:2.3:o:redhat:enterprise_linux_for_power_little_endian_eus:8.4:*:*:*:*:*:*:* | ||
| cpe:2.3:o:redhat:enterprise_linux_server_aus:8.4:*:*:*:*:*:*:* |
To consult the complete list of CPE names with products and versions, see this page
References to Advisories, Solutions, and Tools
- https://bugs.python.org/issue43075
- https://bugzilla.redhat.com/show_bug.cgi?id=1995234
- https://github.com/python/cpython/commit/7215d1ae25525c92b026166f9d5cac85fb
- https://github.com/python/cpython/pull/24391
- https://lists.debian.org/debian-lts-announce/2023/05/msg00024.html
- https://lists.debian.org/debian-lts-announce/2023/06/msg00039.html
- https://security.netapp.com/advisory/ntap-20220407-0001/
- https://ubuntu.com/security/CVE-2021-3733
- https://bugs.python.org/issue43075
- https://bugzilla.redhat.com/show_bug.cgi?id=1995234
- https://github.com/python/cpython/commit/7215d1ae25525c92b026166f9d5cac85fb
- https://github.com/python/cpython/pull/24391
- https://lists.debian.org/debian-lts-announce/2023/05/msg00024.html
- https://lists.debian.org/debian-lts-announce/2023/06/msg00039.html
- https://lists.debian.org/debian-lts-announce/2024/12/msg00000.html
- https://security.netapp.com/advisory/ntap-20220407-0001/
- https://ubuntu.com/security/CVE-2021-3733



