Rapid7

vulnerability

Ubuntu: (Multiple Advisories) (CVE-2019-12523): Squid vulnerabilities

Severity
6
CVSS
(AV:N/AC:L/Au:N/C:P/I:P/A:N)
Published
Nov 14, 2019
Added
Dec 5, 2019
Modified
Mar 27, 2026

Description

An issue was discovered in Squid before 4.9. When handling a URN request, a corresponding HTTP request is made. This HTTP request doesn't go through the access checks that incoming HTTP requests go through. This causes all access checks to be bypassed and allows access to restricted HTTP servers, e.g., an attacker can connect to HTTP servers that only listen on localhost.

Solution

ubuntu-upgrade-squid
Title
Rapid7 Labs

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