CVE-2021-23336 Web Cache Poisoning
Attackers can poison web caches by exploiting semicolon parameter parsing differences in Python's urllib, leading to security bypasses.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is CVE-2021-23336?
CVE-2021-23336 is a medium-severity vulnerability in Debian Debian Linux, published on 15 Feb 2021. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Official description
The package python/cpython from 0 and before 3.6.13, from 3.7.0 and before 3.7.10, from 3.8.0 and before 3.8.8, from 3.9.0 and before 3.9.2 are vulnerable to Web Cache Poisoning via urllib.parse.parse_qsl and urllib.parse.parse_qs by using a vector called parameter cloaking. When the attacker can separate query parameters using a semicolon (;), they can cause a difference in the interpretation of the request between the proxy (running with default configuration) and the server. This can result in malicious requests being cached as completely safe ones, as the proxy would usually not see the semicolon as a separator, and therefore would not include it in a cache key of an unkeyed parameter.
Weakness: CWE-444
Which versions are affected by CVE-2021-23336?
4 open source packages ship an affected version, including django, libpython and python. It affects 12 products.
| Package | Affected | Fixed in |
|---|---|---|
django Bitnami | From 2.2.0 | 2.2.19, 3.0.13, 3.1.7 |
libpython Bitnami | All versions | 3.6.13, 3.7.10, 3.8.8, 3.9.2 |
python Bitnami | All versions | 3.6.13, 3.7.10, 3.8.8, 3.9.2 |
python-min Bitnami | All versions | 3.6.13, 3.7.10, 3.8.8, 3.9.2 |
Linux distribution packages (36)
python SUSE:Enterprise Storage 6 | All versions | 2.7.18-7.55.1 |
python-base SUSE:Enterprise Storage 6 | All versions | 2.7.18-7.55.1 |
python SUSE:Linux Enterprise High Performance Computing 15 SP1-ESPOS | All versions | 2.7.18-7.55.1 |
python-base SUSE:Linux Enterprise High Performance Computing 15 SP1-ESPOS | All versions | 2.7.18-7.55.1 |
python SUSE:Linux Enterprise High Performance Computing 15 SP1-LTSS | All versions | 2.7.18-7.55.1 |
python-base SUSE:Linux Enterprise High Performance Computing 15 SP1-LTSS | All versions | 2.7.18-7.55.1 |
python SUSE:Linux Enterprise High Performance Computing 15-ESPOS | All versions | 2.7.18-7.55.1 |
python-base SUSE:Linux Enterprise High Performance Computing 15-ESPOS | All versions | 2.7.18-7.55.1 |
python SUSE:Linux Enterprise High Performance Computing 15-LTSS | All versions | 2.7.18-7.55.1 |
python-base SUSE:Linux Enterprise High Performance Computing 15-LTSS | All versions | 2.7.18-7.55.1 |
python3 SUSE:Linux Enterprise Micro 5.0 | All versions | 3.6.13-3.78.1 |
python3-core SUSE:Linux Enterprise Micro 5.0 | All versions | 3.6.13-3.78.1 |
python SUSE:Linux Enterprise Module for Basesystem 15 SP2 | All versions | 2.7.18-7.55.1 |
python-base SUSE:Linux Enterprise Module for Basesystem 15 SP2 | All versions | 2.7.18-7.55.1 |
python3 SUSE:Linux Enterprise Module for Basesystem 15 SP2 | All versions | 3.6.13-3.78.1 |
python3-core SUSE:Linux Enterprise Module for Basesystem 15 SP2 | All versions | 3.6.13-3.78.1 |
python SUSE:Linux Enterprise Module for Desktop Applications 15 SP2 | All versions | 2.7.18-7.55.1 |
python3-core SUSE:Linux Enterprise Module for Development Tools 15 SP2 | All versions | 3.6.13-3.78.1 |
python SUSE:Linux Enterprise Module for Python 2 15 SP2 | All versions | 2.7.18-7.55.1 |
python-base SUSE:Linux Enterprise Module for Python 2 15 SP2 | All versions | 2.7.18-7.55.1 |
python3 SUSE:Linux Enterprise Module for Web and Scripting 12 | All versions | 3.4.10-25.66.1 |
python3-base SUSE:Linux Enterprise Module for Web and Scripting 12 | All versions | 3.4.10-25.66.1 |
python3 SUSE:Linux Enterprise Server 12 SP5 | All versions | 3.4.10-25.66.1 |
python3-base SUSE:Linux Enterprise Server 12 SP5 | All versions | 3.4.10-25.66.1 |
python36 SUSE:Linux Enterprise Server 12 SP5 | All versions | 3.6.13-4.36.1 |
python36-core SUSE:Linux Enterprise Server 12 SP5 | All versions | 3.6.13-4.36.1 |
python SUSE:Linux Enterprise Server 15 SP1-BCL | All versions | 2.7.18-7.55.1 |
python-base SUSE:Linux Enterprise Server 15 SP1-BCL | All versions | 2.7.18-7.55.1 |
python SUSE:Linux Enterprise Server 15 SP1-LTSS | All versions | 2.7.18-7.55.1 |
python-base SUSE:Linux Enterprise Server 15 SP1-LTSS | All versions | 2.7.18-7.55.1 |
python SUSE:Linux Enterprise Server 15-LTSS | All versions | 2.7.18-7.55.1 |
python-base SUSE:Linux Enterprise Server 15-LTSS | All versions | 2.7.18-7.55.1 |
python3 SUSE:Linux Enterprise Server for SAP Applications 12 SP5 | All versions | 3.4.10-25.66.1 |
python3-base SUSE:Linux Enterprise Server for SAP Applications 12 SP5 | All versions | 3.4.10-25.66.1 |
python36 SUSE:Linux Enterprise Server for SAP Applications 12 SP5 | All versions | 3.6.13-4.36.1 |
python36-core SUSE:Linux Enterprise Server for SAP Applications 12 SP5 | All versions | 3.6.13-4.36.1 |
Products include Debian Debian Linux, Djangoproject Django, Fedoraproject Fedora, Netapp Cloud Backup, Netapp Inventory Collect Tool, Netapp Ontap Select Deploy Administration Utility and 6 more.
How do I fix CVE-2021-23336?
Upgrade django to a fixed version for your release line: 2.2.19, 3.0.13 or 3.1.7.
Is CVE-2021-23336 being exploited?
There is no known exploitation of CVE-2021-23336 in the wild and no public exploit code.
Other vulnerabilities in Debian Debian Linux
Sources
Also known as ALPINE-CVE-2021-23336, AZL-109632, AZL-6827, AZL-84275, BIT-django-2021-23336, BIT-libpython-2021-23336 and 23 more.