OTPulse

Siemens SINEMA Remote Connect Server

Plan PatchCVSS 9.8ICS-CERT ICSA-24-074-03Mar 12, 2024
Siemens
Attack path
Attack VectorNetwork
Auth RequiredNone
ComplexityLow
User InteractionNone needed
Summary

SINEMA Remote Connect Server before version 3.2 contains multiple vulnerabilities including input validation flaws (CWE-79) and insufficient access control (CWE-284). These allow an unauthenticated attacker with network access to execute arbitrary code and bypass authentication mechanisms on the server. The vulnerability affects all remote connections managed through the server and could allow unauthorized access to engineering workstations and industrial control systems connected via this remote access solution.

What this means
What could happen
An attacker with network access to SINEMA Remote Connect Server could execute arbitrary code, gain unauthorized access to sensitive configuration data, or manipulate remote access credentials, potentially allowing unauthorized connection to industrial control systems and engineering workstations.
Who's at risk
This affects organizations using Siemens SINEMA Remote Connect Server for remote access to engineering workstations and PLCs. This is critical for utilities, water authorities, and manufacturers that rely on remote engineering access to configure or troubleshoot Siemens automation systems. Anyone managing remote connections to industrial control systems should prioritize this update.
How it could be exploited
An attacker on the network sends a specially crafted request to the unauthenticated web interface of SINEMA Remote Connect Server. The server processes the request without proper input validation (CWE-79) or access control (CWE-284), allowing the attacker to inject code or bypass authentication. The attacker gains remote code execution on the server and can then access or modify remote connection credentials and engineering workstation configurations.
Prerequisites
  • Network access to the SINEMA Remote Connect Server web interface (typically port 443)
  • No authentication required to trigger the vulnerability
  • Server must be running an affected version (below V3.2)
remotely exploitableno authentication requiredlow complexity attackhigh CVSS score (9.8)affects remote access to ICS systems
Exploitability
Unlikely to be exploited — EPSS score 0.4%
Affected products (2)
2 with fix
ProductAffected VersionsFix Status
SINEMA Remote Connect Server<V3.13.1
SINEMA Remote Connect Server<V3.23.2
Remediation & Mitigation
0/4
Do now
0/1
SINEMA Remote Connect Server
WORKAROUNDIf immediate patching is not possible, restrict network access to SINEMA Remote Connect Server through firewall rules to allow only authorized engineering workstations and IT management systems
Schedule — requires maintenance window
0/2

Patching may require device reboot — plan for process interruption

SINEMA Remote Connect Server
HOTFIXUpdate SINEMA Remote Connect Server to version 3.2 or later immediately
HARDENINGReview and audit all remote access connections and credential management in SINEMA Remote Connect Server logs to identify any unauthorized access
Long-term hardening
0/1
SINEMA Remote Connect Server
HARDENINGImplement network segmentation to isolate the SINEMA Remote Connect Server from general corporate network access
View full CISA ICS-CERT advisory
API: /api/v1/advisories/df9cb93f-2c71-419e-841d-9865bf73ccd4

Get OT security insights every Tuesday

Advisory breakdowns, a weekly summary, and incident analyses for the people actually defending OT environments. Free, no account required.