CVE-2021-23336

MEDIUM severity · CVSS 5.9 · CWE-444

5.9CVSS MEDIUM

Summary

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.

Impact & exploitability

Attack vectorNetwork

Attack complexityHigh

Privileges requiredNone

User interactionRequired

Confidentiality impactNone

Integrity impactLow

Availability impactHigh

Exploit probability (EPSS)0%

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

Affected products we track (2)

Python Django

Recommendation

Apply the vendor fix in your normal patch cycle. Open any affected product above for its exact safe version.

Official patch: http://www.openwall.com/lists/oss-security/2021/02/19/4 ↗

CVE-2021-23336

Summary

Impact & exploitability

Affected products we track (2)

Recommendation

Additional information