CVE-2024-27941: Siemens Ruggedcom Crossbow SQLI Vulnerability

CVE-2024-27941 Overview

CVE-2024-27941 is a SQL injection vulnerability affecting Siemens RUGGEDCOM CROSSBOW client systems in all versions prior to V5.5. The affected client applications fail to sanitize input data before transmitting it to the backend SQL server. An authenticated attacker with low privileges can inject malicious SQL statements over the network to compromise the entire database. The flaw is tracked under CWE-89 (Improper Neutralization of Special Elements used in an SQL Command).

Critical Impact
Successful exploitation allows attackers to read, modify, or destroy any data stored in the RUGGEDCOM CROSSBOW database, undermining confidentiality, integrity, and availability of the Station Access Controller platform used in critical infrastructure environments.

Affected Products

Siemens RUGGEDCOM CROSSBOW: All versions prior to V5.5
Siemens RUGGEDCOM CROSSBOW Station Access Controller client
Substation automation and remote access deployments using vulnerable RUGGEDCOM CROSSBOW client builds

Discovery Timeline

2024-05-14 - CVE-2024-27941 published to NVD alongside Siemens Security Advisory SSA-916916
2026-06-17 - Last updated in NVD database

Technical Details for CVE-2024-27941

Vulnerability Analysis

RUGGEDCOM CROSSBOW is a Siemens platform used to manage secure remote access to substation intelligent electronic devices (IEDs). The client component builds SQL queries using attacker-controllable input without applying proper parameterization or escaping. When these queries are sent to the backend SQL server, injected statements execute in the database context.

An attacker with valid low-privileged credentials can supply crafted values through client-side fields that are concatenated directly into SQL statements. The server trusts the client-composed query, allowing arbitrary read, write, or schema-manipulation operations against the CROSSBOW database.

Root Cause

The root cause is missing input neutralization on the client, classified as CWE-89. Query strings are constructed by concatenating user-supplied data rather than using parameterized statements or prepared queries with strict typing.

Attack Vector

Exploitation requires network reachability to the CROSSBOW client interface and valid authenticated access at low privilege. No user interaction is required. Because CROSSBOW mediates access to substation equipment, database compromise can expose device credentials, access policies, audit logs, and connection configurations that support downstream operational technology (OT) attacks.

No verified exploit code, proof-of-concept, or entry in the CISA Known Exploited Vulnerabilities catalog is currently published. Refer to the Siemens ProductCERT advisory SSA-916916 for authoritative technical details.

Detection Methods for CVE-2024-27941

Indicators of Compromise

Unexpected SQL syntax fragments such as ' OR 1=1--, UNION SELECT, or stacked queries in CROSSBOW client logs or database audit trails
Anomalous database queries originating from CROSSBOW client accounts, particularly against sys or metadata tables
Creation, modification, or deletion of database users, roles, or stored procedures outside change windows
Outbound connections from the CROSSBOW database host to untrusted destinations following authenticated client sessions

Detection Strategies

Enable SQL Server auditing on the CROSSBOW backend database and alert on statements containing injection primitives or schema-altering DDL from application accounts.
Correlate CROSSBOW authentication events with database query volume to identify sessions that generate abnormal query patterns.
Baseline normal CROSSBOW client-to-database traffic and flag deviations in query length, frequency, or table scope.

Monitoring Recommendations

Forward CROSSBOW application logs and SQL Server audit logs to a centralized SIEM for correlation with identity and network telemetry.
Monitor for privilege changes on the CROSSBOW database service account and any use of xp_cmdshell or equivalent extended procedures.
Track failed and successful logins to the CROSSBOW client from unexpected source addresses inside the OT management network.

How to Mitigate CVE-2024-27941

Immediate Actions Required

Upgrade all RUGGEDCOM CROSSBOW installations to V5.5 or later as directed by Siemens Security Advisory SSA-916916.
Restrict network access to the CROSSBOW client and its database server to trusted engineering workstations and jump hosts only.
Rotate credentials for CROSSBOW user accounts and the database service account after patching.
Review database audit logs for suspicious queries executed prior to remediation.

Patch Information

Siemens has released RUGGEDCOM CROSSBOW V5.5, which remediates CVE-2024-27941. Customers should download the fixed version from the Siemens Industry Online Support portal and follow the upgrade guidance in advisory SSA-916916. Apply the update on both server and client components to ensure the sanitization fix is effective across all query paths.

Workarounds

Segment the CROSSBOW server and client hosts within a dedicated OT management VLAN protected by a stateful firewall following the Siemens Operational Guidelines for Industrial Security.
Enforce least-privilege database roles so CROSSBOW application accounts cannot execute DDL or access system catalogs.
Require multi-factor authentication and jump-host access for any administrator interacting with CROSSBOW clients until patching is complete.
Enable database-layer query filtering or a web/database application firewall to block common SQL injection patterns.

bash

# Example: restrict CROSSBOW database access with least-privilege role
# (adapt to your SQL Server environment before deployment)
CREATE ROLE crossbow_app_ro;
GRANT SELECT, INSERT, UPDATE ON SCHEMA::crossbow TO crossbow_app_ro;
DENY ALTER, CONTROL, EXECUTE ON SCHEMA::sys TO crossbow_app_ro;
ALTER SERVER ROLE sysadmin DROP MEMBER crossbow_service;