CVE-2021-23336

Public on 2021-05-06
Modified on 2021-05-24
Description
The package python/cpython is 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.
Severity
Medium
CVSS v3 Base Score
5.9
See breakdown

Affected Packages

Platform Package Release Date Advisory
Amazon Linux 2 python3 2021-05-20 16:15 ALAS2-2021-1640
Amazon Linux 1 python35 2021-05-06 19:11 ALAS-2021-1498
Amazon Linux 1 python36 2021-05-14 16:53 ALAS-2021-1500
Amazon Linux 1 python34 2021-05-20 21:12 ALAS-2021-1504

CVSS Scores

Score Type Score Vector
Amazon Linux CVSSv3 5.9 CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:L/A:H
NVD CVSSv2 4.0 AV:N/AC:H/Au:N/C:N/I:P/A:P
NVD CVSSv3 5.9 CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:L/A:H