Overview
In the cybersecurity landscape, a new threat has emerged that has potential to compromise systems or lead to data leakage. This vulnerability, identified as CVE-2025-26846, is a major concern particularly for users of Znuny, a popular open-source helpdesk and IT service management (ITSM) solution. The flaw resides in versions of Znuny before 7.1.4 and puts at risk any organization that uses this software to manage their customer support and IT service needs.
The vulnerability is significant due to its high CVSS Severity Score of 9.8, indicating that it can have a critical impact on systems, and because it bypasses the permission checks when updating ticket metadata. This could allow an attacker to manipulate the system in an unauthorized manner, which can lead to system compromise or data leakage if not promptly addressed.
Vulnerability Summary
CVE ID: CVE-2025-26846
Severity: Critical – CVSS 9.8
Attack Vector: Network
Privileges Required: None
User Interaction: None
Impact: System compromise or data leakage
Affected Products
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Product | Affected Versions
Znuny | Before 7.1.4
How the Exploit Works
The vulnerability occurs due to insufficient permission checks when using the Generic Interface to update ticket metadata within Znuny. This means an unauthenticated attacker could exploit this flaw by sending a carefully crafted request to the Generic Interface, thereby manipulating ticket metadata in an unauthorized manner.
Conceptual Example Code
Below is a
conceptual
example of how the vulnerability might be exploited. This example involves a malicious HTTP request that is sent to the Generic Interface.
POST /znuny/generic/updateTicket HTTP/1.1
Host: target.example.com
Content-Type: application/json
{
"TicketID": "12345",
"Subject": "Malicious Subject",
"DataLeak": "Sensitive Data..."
}In this example, the attacker is exploiting the vulnerability by sending a malicious POST request to the ‘updateTicket’ endpoint of the Generic Interface. They are updating the Subject and potentially adding sensitive data to the ticket without proper authorization.
Mitigation and Prevention
Users are strongly advised to upgrade to Znuny version 7.1.4 or later, which contains a fix for this vulnerability. If immediate patching is not possible, organizations can utilize a Web Application Firewall (WAF) or Intrusion Detection System (IDS) as a temporary mitigation measure. However, these should not be seen as long-term solutions, and systems should be patched as soon as possible to close this serious security vulnerability.