CVE-2025-15068: Gmission Web Fax Auth Bypass Vulnerability

CVE-2025-15068 Overview

CVE-2025-15068 is a Missing Authorization vulnerability affecting Gmission Web Fax that enables Authentication Abuse and Session Credential Falsification through Manipulation. This flaw allows attackers to bypass authorization controls to abuse authentication mechanisms and falsify session credentials, potentially gaining unauthorized access to the fax application and its resources.

Critical Impact

Attackers can exploit this missing authorization flaw to bypass authentication controls and manipulate session credentials, potentially compromising the confidentiality and integrity of fax communications and associated data.

Affected Products

• Gmission Web Fax versions 3.0 before 3.0.1

Discovery Timeline

• 2025-12-29 - CVE CVE-2025-15068 published to NVD
• 2026-01-13 - Last updated in NVD database

Technical Details for CVE-2025-15068

Vulnerability Analysis

This vulnerability stems from a Missing Authorization weakness (CWE-862) in Gmission Web Fax. The application fails to properly verify that a user has the necessary permissions to perform a requested action, allowing attackers to bypass authentication mechanisms entirely. The flaw requires local access to exploit, but once access is obtained, no user interaction or privileges are required to manipulate session credentials. The vulnerability impacts both confidentiality and integrity, meaning attackers can both access sensitive data and modify system state without proper authorization.

Root Cause

The root cause is the absence of proper authorization checks within the Gmission Web Fax application's authentication handling logic. When processing session credentials and authentication requests, the application does not adequately validate that the requesting entity has the appropriate permissions. This allows manipulation of session tokens or credentials without triggering security controls that would normally prevent unauthorized access.

Attack Vector

The attack vector is local (AV:L), requiring the attacker to have some level of local access to the target system or network where Gmission Web Fax is deployed. Once local access is achieved, the attacker can:

1. Intercept or manipulate session credentials through the vulnerable authentication mechanism
2. Falsify session tokens to impersonate legitimate users
3. Bypass authorization controls to access protected fax resources and communications
4. Potentially escalate access by abusing the compromised authentication state

The attack requires low complexity (AC:L), no special privileges (PR:N), and no user interaction (UI:N), making it relatively straightforward to exploit once local access is obtained.

Detection Methods for CVE-2025-15068

Indicators of Compromise

• Unusual session creation patterns or multiple sessions originating from unexpected sources
• Authentication log entries showing access without corresponding valid credential submissions
• Anomalous session credential values or malformed session tokens in application logs
• Unexpected access to fax resources by users who should not have permissions

Detection Strategies

• Monitor authentication and session management logs for credential manipulation attempts
• Implement anomaly detection for session token patterns that deviate from normal baseline behavior
• Deploy network monitoring to identify local access attempts to the Web Fax application
• Review access control logs for unauthorized resource access following authentication events

Monitoring Recommendations

• Enable verbose logging on the Gmission Web Fax application for authentication events
• Set up alerts for failed authentication attempts followed by successful access
• Monitor for session fixation patterns where session IDs are reused inappropriately
• Implement SIEM rules to correlate authentication anomalies with subsequent resource access

How to Mitigate CVE-2025-15068

Immediate Actions Required

• Upgrade Gmission Web Fax to version 3.0.1 or later immediately
• Review existing session logs for signs of prior exploitation
• Restrict local access to systems running Gmission Web Fax to authorized personnel only
• Implement network segmentation to limit exposure of the fax application

Patch Information

Gmission has addressed this vulnerability in Web Fax version 3.0.1. Organizations running affected versions (3.0 before 3.0.1) should upgrade to the patched version as soon as possible. For additional information, consult the Gmission Resource Page.

Workarounds

• Implement additional network-level access controls to restrict local access to the Web Fax application
• Deploy web application firewall (WAF) rules to monitor and filter suspicious session manipulation attempts
• Enable multi-factor authentication (MFA) if supported to add an additional layer of verification
• Conduct regular session audits and implement session timeout policies to limit exposure window

# Configuration example - Restrict local network access to Web Fax service
# Add firewall rules to limit access to trusted IP ranges only
# Example using iptables (adjust interface and IP ranges as needed)
iptables -A INPUT -p tcp --dport 80 -s 192.168.1.0/24 -j ACCEPT
iptables -A INPUT -p tcp --dport 443 -s 192.168.1.0/24 -j ACCEPT
iptables -A INPUT -p tcp --dport 80 -j DROP
iptables -A INPUT -p tcp --dport 443 -j DROP