#VU22908 Input validation error in Squid - CVE-2019-12523

Vulnerability identifier: #VU22908

Vulnerability risk: Medium

CVSSv4.0: 1.3 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2019-12523

CWE-ID: CWE-20

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Squid
Server applications / IDS/IPS systems, Firewalls and proxy servers

Vendor: Squid-cache.org

Description

The vulnerability allows a remote attacker to bypass certain security restrictions.

The vulnerability exists due to insufficient validation of user-supplied input when processing URIs. A remote authenticated attacker can add certain characters to the URI, bypass implemented security restrictions and access restricted websites.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Squid: 3.0.stable1 - 3.5.28, 4.0.1 - 4.8

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External links
https://www.squid-cache.org/Advisories/SQUID-2019_8.txt

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote authenticated user via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.