CVE-2021-23336

MEDIUMCVSS 5.9/10EPSS 35.96%

Last modified

CVE-2021-23336 is a medium-severity vulnerability rated 5.9/10 on the CVSS scale. 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. EPSS estimates a 35.96% chance of exploitation in the next 30 days.

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.

Metrics

CVSS 3.1
5.9/10

CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:L/A:H

EPSS Probability
35.96%

98.3th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

VendorProductVersions
PythonPython< 3.6.13
PythonPython>= 3.7.0, < 3.7.10
PythonPython>= 3.8.0, < 3.8.8
PythonPython>= 3.9.0, < 3.9.2
FedoraprojectFedora32
FedoraprojectFedora33
FedoraprojectFedora34
DebianDebian Linux9.0
NetappCloud BackupAll versions
NetappInventory Collect ToolAll versions
NetappOntap Select Deploy Administration UtilityAll versions
NetappSnapcenterAll versions
DjangoprojectDjango>= 2.2, < 2.2.19
DjangoprojectDjango>= 3.0, < 3.0.13
DjangoprojectDjango>= 3.1, < 3.1.7
OracleCommunications Offline Mediation Controller12.0.0.3.0
OracleCommunications Pricing Design Center12.0.0.3.0
OracleEnterprise Manager Ops Center12.4.0.0
OracleZfs Storage Appliance8.8

References

Timeline

Published
Last Modified
Status
Modified

Frequently Asked Questions

What is CVE-2021-23336?
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.
How severe is CVE-2021-23336?
CVE-2021-23336 has a CVSS score of 5.9/10 (MEDIUM severity). The EPSS model estimates a 35.96% probability of exploitation in the next 30 days.
How do I fix CVE-2021-23336?
Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2021-23336?

Run a free Strix scan to check your systems for this vulnerability.

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Source: NVD / NIST