#VU22254 Improper access control in FusionPBX - CVE-2019-16990

Vulnerability identifier: #VU22254

Vulnerability risk: Medium

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

CVE-ID: CVE-2019-16990

CWE-ID: CWE-284

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
FusionPBX
Server applications / SCADA systems

Vendor: FusionPBX

Description

The vulnerability allows a remote attacker to gain unauthorized access to otherwise restricted functionality.

The vulnerability exists due to improper access restrictions in app/music_on_hold/music_on_hold.php file when processing base64-encoded file names. A remote authenticated user can pass a base64-encoded filename to the application and download any pathname on the system.

Mitigation
Install updates released on 15/08/2019 on 4.4 and Master branches.

Vulnerable software versions

FusionPBX: Master

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External links
https://github.com/fusionpbx/fusionpbx/commit/95ed18aa9d781f232f5686a9027bb6f677c9b8da
https://resp3ctblog.wordpress.com/2019/10/19/fusionpbx-path-traversal-3/

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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.