#VU109018 Path traversal in Output Messenger - CVE-2025-27920

Vulnerability identifier: #VU109018

Vulnerability risk: High

CVSSv4.0: 8.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:A/U:Amber]

CVE-ID: CVE-2025-27920

CWE-ID: CWE-22

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Output Messenger
Server applications / Conferencing, Collaboration and VoIP solutions

Vendor: Srimax Software System

Description

The vulnerability allows a remote user to perform directory traversal attacks.

The vulnerability exists due to input validation error when processing directory traversal sequences. A remote authenticated user can upload malicious files to an arbitrary location on the system and execute them, leading to full system compromise.

Note, the vulnerability is being actively exploited in the wild.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Output Messenger: 1.0.65 - 2.0.62

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External links
https://www.outputmessenger.com/cve-2025-27920/
https://www.microsoft.com/en-us/security/blog/2025/05/12/marbled-dust-leverages-zero-day-in-output-messenger-for-regional-espionage/

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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?

Yes. This vulnerability is being exploited in the wild.