CVE-2025-32831: Siemens Telecontrol Server Basic SQLi

CVE-2025-32831 Overview

CVE-2025-32831 is a SQL injection vulnerability affecting Siemens TeleControl Server Basic versions prior to V3.1.2.2. The flaw resides in the internally used UpdateProjectUserRights method. An authenticated remote attacker who can reach TCP port 8000 can bypass authorization controls, read and modify the application database, and execute code under the NT AUTHORITY\NetworkService account. The weakness is classified under CWE-89: Improper Neutralization of Special Elements used in an SQL Command. Siemens published advisory SSA-443402 describing the issue and providing fixed versions.

Critical Impact
Authenticated attackers with network access to port 8000 can execute arbitrary code as NT AUTHORITY\NetworkService and gain full read/write access to the underlying database.

Affected Products

Siemens TeleControl Server Basic — all versions prior to V3.1.2.2
Deployments exposing TCP port 8000 to remote networks
Windows hosts running the TeleControl Server Basic service account NT AUTHORITY\NetworkService

Discovery Timeline

2025-04-16 - CVE-2025-32831 published to NVD
2025-08-19 - Last updated in NVD database

Technical Details for CVE-2025-32831

Vulnerability Analysis

The vulnerability stems from improper neutralization of user-controlled input passed into the UpdateProjectUserRights method. The method constructs SQL statements that incorporate attacker-supplied data without sufficient sanitization or parameterization. Because the method is reachable by any authenticated client connecting to the TeleControl Server Basic service on port 8000, low-privileged users can manipulate the resulting queries.

Successful exploitation allows the attacker to bypass the application's authorization checks. The attacker can then issue arbitrary SQL statements against the back-end database, read sensitive project and user data, and modify records that govern access control. Because the service runs under the NT AUTHORITY\NetworkService Windows account, the attacker can pivot from SQL execution to operating system command execution within that security context.

Root Cause

The root cause is a failure to use parameterized queries or strict input validation within the UpdateProjectUserRights server-side method. Authorization logic relies on values that are themselves subject to manipulation through the injectable query path, allowing the attacker to elevate effective permissions inside the application.

Attack Vector

The attack vector is network-based. The attacker authenticates to the TeleControl Server Basic service on TCP port 8000 with low-privilege credentials, then invokes the vulnerable internal method with crafted parameters. The injected SQL is processed by the database engine, returning data or triggering write operations the calling user is not entitled to perform. Code execution under NetworkService follows from database-level features and the host service context.

Siemens has not published proof-of-concept code, and no public exploit is currently available for CVE-2025-32831. Refer to Siemens Security Advisory SSA-443402 for vendor-confirmed technical details.

Detection Methods for CVE-2025-32831

Indicators of Compromise

Unexpected authenticated sessions originating from non-engineering networks to TCP port 8000 on TeleControl Server Basic hosts.
Anomalous SQL statements in database logs containing UNION, semicolons, or stacked queries originating from the UpdateProjectUserRights call path.
Process creation events from the TeleControl service running as NT AUTHORITY\NetworkService spawning shells, scripting hosts, or network utilities.
Modifications to user-rights or project tables that do not correlate with administrator activity.

Detection Strategies

Enable verbose application and database query logging on TeleControl Server Basic and review queries referencing user rights tables for injection patterns.
Inspect Windows Security and Sysmon logs for child processes of the TeleControl service binary running under NetworkService.
Correlate authentication events on port 8000 with subsequent database write activity to identify privilege escalation attempts.

Monitoring Recommendations

Restrict and monitor inbound connections to TCP port 8000 using network segmentation and firewall allow-lists.
Forward TeleControl Server Basic, Windows, and SQL telemetry to a centralized SIEM for correlation and retention.
Alert on any new process executed by the NetworkService account on TeleControl hosts, especially cmd.exe, powershell.exe, or rundll32.exe.

How to Mitigate CVE-2025-32831

Immediate Actions Required

Upgrade TeleControl Server Basic to version V3.1.2.2 or later as directed in Siemens advisory SSA-443402.
Restrict network access to TCP port 8000 so only trusted engineering workstations can reach the service.
Rotate credentials for all TeleControl users and review the user-rights tables for unauthorized modifications.
Audit the host for unexpected processes or persistence created under the NT AUTHORITY\NetworkService account.

Patch Information

Siemens addresses CVE-2025-32831 in TeleControl Server Basic V3.1.2.2. Apply the update on every affected host and validate the version after installation. Consult Siemens Security Advisory SSA-443402 for download links, hashes, and operational notes.

Workarounds

Place TeleControl Server Basic behind a firewall and limit port 8000 access to a dedicated management VLAN.
Apply the principle of least privilege to TeleControl application accounts and disable unused user accounts.
Where patching is delayed, monitor authentication and database activity continuously and isolate the server from general corporate networks.

bash

# Example Windows Firewall rule restricting access to port 8000
netsh advfirewall firewall add rule name="TeleControl-8000-Allowlist" \
  dir=in action=allow protocol=TCP localport=8000 \
  remoteip=10.10.20.0/24

netsh advfirewall firewall add rule name="TeleControl-8000-Block" \
  dir=in action=block protocol=TCP localport=8000