CVE-2026-2039 Overview
CVE-2026-2039 is a critical authentication bypass vulnerability affecting GFI Archiver. The vulnerability exists within the MArc.Store.Remoting.exe process, which listens on TCP port 8018 and lacks proper authorization controls. Remote attackers can exploit this flaw without any authentication to bypass security controls and, when chained with other vulnerabilities, potentially achieve code execution in the context of SYSTEM.
Critical Impact
Remote attackers can bypass authentication on affected GFI Archiver installations without any credentials, potentially leading to complete system compromise when combined with additional vulnerabilities.
Affected Products
- GFI Archiver version 15.10
- Systems running MArc.Store.Remoting.exe service on port 8018
Discovery Timeline
- 2026-02-20 - CVE-2026-2039 published to NVD
- 2026-02-24 - Last updated in NVD database
Technical Details for CVE-2026-2039
Vulnerability Analysis
This vulnerability is classified as CWE-862 (Missing Authorization), representing a fundamental security control failure in the GFI Archiver application. The MArc.Store.Remoting.exe component exposes functionality over the network on port 8018 without implementing proper authorization checks.
The absence of authorization controls means that any network-accessible attacker can interact with the exposed service functionality. This design flaw allows attackers to bypass the authentication mechanisms entirely, gaining access to protected features without providing valid credentials. The vulnerability is particularly severe because it can serve as an entry point for attack chains that ultimately lead to SYSTEM-level code execution.
Root Cause
The root cause lies in the configuration and implementation of the MArc.Store.Remoting.exe process. The service was deployed without enforcing authorization checks before granting access to its exposed functionality. This missing authorization check (CWE-862) allows unauthenticated remote connections to interact with sensitive application features that should be protected behind authentication barriers.
Attack Vector
The attack vector is network-based, requiring no user interaction or prior authentication. An attacker with network access to port 8018 on a vulnerable GFI Archiver installation can directly connect to the MArc.Store.Remoting.exe service and leverage the missing authorization flaw.
The exploitation path involves:
- Identifying a GFI Archiver installation with port 8018 accessible
- Connecting to the MArc.Store.Remoting.exe service
- Bypassing authentication due to missing authorization controls
- Chaining with additional vulnerabilities to achieve code execution as SYSTEM
For detailed technical analysis, refer to the Zero Day Initiative Advisory ZDI-26-077.
Detection Methods for CVE-2026-2039
Indicators of Compromise
- Unexpected network connections to port 8018 from external or unauthorized IP addresses
- Anomalous process activity associated with MArc.Store.Remoting.exe
- Unauthorized access attempts or authentication bypass events in GFI Archiver logs
- Unusual SYSTEM-level process spawning linked to GFI Archiver components
Detection Strategies
- Monitor network traffic to TCP port 8018 for unauthorized connection attempts
- Implement IDS/IPS rules to detect exploitation patterns targeting the MArc.Store service
- Review Windows Security Event logs for anomalous process creation under SYSTEM context originating from GFI Archiver processes
- Deploy network segmentation to restrict access to port 8018 from untrusted networks
Monitoring Recommendations
- Enable detailed logging for the GFI Archiver application and associated services
- Configure SIEM alerts for unusual access patterns to the MArc.Store.Remoting.exe service
- Implement continuous vulnerability scanning to identify unpatched GFI Archiver instances
- Monitor for lateral movement indicators following potential exploitation
How to Mitigate CVE-2026-2039
Immediate Actions Required
- Restrict network access to port 8018 using firewall rules, limiting connections to trusted administrative hosts only
- Isolate affected GFI Archiver servers from untrusted network segments
- Review GFI vendor communications for available security patches and apply them immediately
- Audit existing GFI Archiver installations to identify all potentially vulnerable deployments
Patch Information
Consult the Zero Day Initiative Advisory ZDI-26-077 and GFI vendor resources for official patch availability. Organizations should prioritize patching due to the critical nature of this vulnerability and its potential for exploitation in attack chains leading to SYSTEM-level compromise.
Workarounds
- Block inbound connections to TCP port 8018 from untrusted networks using host-based or network firewalls
- Implement network segmentation to isolate GFI Archiver servers from general network traffic
- Consider temporarily disabling the MArc.Store.Remoting.exe service if the functionality is not critical to operations
- Deploy application whitelisting to prevent unauthorized code execution on GFI Archiver servers
# Example: Block external access to port 8018 using Windows Firewall
netsh advfirewall firewall add rule name="Block GFI Archiver Port 8018" dir=in action=block protocol=TCP localport=8018 remoteip=any
# Allow only trusted management subnet
netsh advfirewall firewall add rule name="Allow GFI Archiver Management" dir=in action=allow protocol=TCP localport=8018 remoteip=10.0.100.0/24
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
