CVE-2019-12524 Information

Description

An issue was discovered in Squid through 4.7. When handling requests from users Squid checks its rules to see if the request should be denied. Squid by default comes with rules to block access to the Cache Manager which serves detailed server information meant for the maintainer. This rule is implemented via url_regex. The handler for url_regex rules URL decodes an incoming request. This allows an attacker to encode their URL to bypass the url_regex check and gain access to the blocked resource.

CVSS Vector

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

Reference

https://gitlab.com/jeriko.one/security/-/blob/master/squid/CVEs/CVE-2019-12524.txt https://lists.debian.org/debian-lts-announce/2020/07/msg00009.html https://usn.ubuntu.com/4446-1/ https://www.debian.org/security/2020/dsa-4682 An issue was discovered in Squid through 4.7. When handling requests from users Squid checks its rules to see if the request should be denied. Squid by default comes with rules to block access to the Cache Manager which serves detailed server information meant for the maintainer. This rule is implemented via url_regex. The handler for url_regex rules URL decodes an incoming request. This allows an attacker to encode their URL to bypass the url_regex check and gain access to the blocked resource.

Attack Complexity

LOW

Privileges Required

NONE

User Interaction Required

NONE

Scope

NONE

Confidentiality Impact

UNCHANGED

Integrity Impact

HIGH

Availability Impact

HIGH

Base Score

HIGH

Base Severity

9.8