Vulnerability identifier: #VU20461

Vulnerability risk: Medium

CVSSv3.1: 6.5 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2019-12854

CWE-ID: CWE-125

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 perform denial of service (DoS) attack.

The vulnerability exists due to a boundary condition when terminating strings in cachemgr.cgi. A remote attacker can a specially crafted request to the affected proxy server, trigger out-of-bounds read error and crash the CGI process, denying access to all users on systems with memory access protections.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Squid: 4.0.1 - 4.7

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External links
http://www.squid-cache.org/Advisories/SQUID-2019_1.txt
http://www.squid-cache.org/Versions/v4/changesets/squid-4-2981a957716c61ff7e21eee1d7d6eb5a237e466d.patch
http://bugs.squid-cache.org/show_bug.cgi?id=4937
http://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/SPXN2CLAGN5QSQBTOV5IGVLDOQSRFNTZ/
http://seclists.org/bugtraq/2019/Aug/42

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

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