CVE-2025-3920 Overview
CVE-2025-3920 is a hard-coded credentials vulnerability in SUR-FBD CMMS, a computerized maintenance management system. Researchers identified that a compiled DLL shipped with the application embeds credentials for a built-in administrative account. An attacker with local access to the host or to the application's installation directory can extract these credentials by inspecting the DLL. Once recovered, the credentials grant full access to the application's administrative functions. The issue is tracked under [CWE-259: Use of Hard-coded Password] and was disclosed through a CERT Poland Advisory CVE-2025-3920. The vendor addressed the flaw in SUR-FBD CMMS version 2025.03.27.
Critical Impact
Extraction of embedded credentials from the DLL yields full administrative control over the CMMS application, exposing maintenance data and workflows to tampering.
Affected Products
- SUR-FBD CMMS versions prior to 2025.03.27
- Installations retaining the vulnerable DLL on disk
- Systems where the SUR-FBD CMMS installation directory is accessible to non-administrative users
Discovery Timeline
- 2025-07-07 - CVE-2025-3920 published to the National Vulnerability Database
- 2026-06-17 - Last updated in NVD database
Technical Details for CVE-2025-3920
Vulnerability Analysis
The flaw stems from credentials that are compiled directly into a DLL distributed with SUR-FBD CMMS. These credentials authenticate a built-in administrative account within the application. Because the values reside in a binary artifact rather than in a protected credential store, any user who can read the DLL can recover them.
Static analysis of the DLL with a disassembler or a strings utility is sufficient to expose the embedded secret. No exploitation tooling or memory corruption primitive is required. Once obtained, the credentials can be replayed against the application's administrative interface to gain full control over records, workflows, and configuration.
Because the account is built-in rather than user-provisioned, administrators cannot rotate or disable it without a vendor-supplied fix. Every deployment of the affected build shares the same secret, which increases risk if the DLL leaks outside the customer environment.
Root Cause
The root cause is a design decision to embed authentication material for a privileged account inside a shipped binary. This pattern is classified under [CWE-259] and violates the principle that secrets must be stored in configurable, protected locations. All installations of a given build inherit the same credential, so a single extraction compromises the entire user base of that version.
Attack Vector
Exploitation requires local access to the host or read access to the installation directory that contains the vulnerable DLL. An attacker with a low-privilege account on the workstation, a share where the installer is staged, or backup media can retrieve the DLL and extract the credential. The attacker then authenticates to the CMMS administrative interface using the recovered secret, gaining full administrative rights within the application.
No verified public proof-of-concept has been released. Refer to the CERT Poland Advisory CVE-2025-3920 for the vendor-coordinated technical details.
Detection Methods for CVE-2025-3920
Indicators of Compromise
- Unexpected logins to the SUR-FBD CMMS administrative account, particularly outside of normal maintenance windows
- Access to the SUR-FBD CMMS installation directory or backup copies of the DLL by non-administrative user accounts
- Presence of reverse-engineering utilities (strings, dnSpy, ILSpy, ghidra) on hosts running SUR-FBD CMMS
Detection Strategies
- Inventory hosts running SUR-FBD CMMS and confirm the installed version against 2025.03.27 or later
- Audit application-level authentication logs for use of the built-in administrative account
- Monitor file-access telemetry on the application's installation directory for reads by unexpected processes or users
Monitoring Recommendations
- Alert on process executions that open the vulnerable DLL outside of the SUR-FBD CMMS runtime
- Correlate administrative CMMS logins with endpoint session data to detect authentication from unexpected users or hosts
- Track configuration changes within CMMS to identify unauthorized administrative activity following the disclosure date
How to Mitigate CVE-2025-3920
Immediate Actions Required
- Upgrade SUR-FBD CMMS to version 2025.03.27 or later on all systems
- Rotate any shared administrative credentials and review recent administrative activity in the CMMS application
- Restrict filesystem permissions on the SUR-FBD CMMS installation directory to administrative accounts only
Patch Information
The vendor addressed the vulnerability in SUR-FBD CMMS version 2025.03.27. Deploy the update to every affected installation and validate that legacy DLLs are removed rather than retained alongside the patched binary. Confirm remediation details in the CERT Poland Advisory CVE-2025-3920.
Workarounds
- Limit interactive and network access to hosts running SUR-FBD CMMS until the patch is applied
- Apply strict access control lists (ACLs) on the installation directory to block read access for non-administrative users
- Isolate CMMS servers on a segmented network and require multi-factor authentication for administrative access to the host
# Example: restrict read access to the SUR-FBD CMMS installation directory on Windows
icacls "C:\Program Files\SUR-FBD CMMS" /inheritance:r
icacls "C:\Program Files\SUR-FBD CMMS" /grant:r "Administrators:(OI)(CI)F" "SYSTEM:(OI)(CI)F"
icacls "C:\Program Files\SUR-FBD CMMS" /remove "Users" "Authenticated Users"
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
