CVE-2024-39865 Siemens CVE debrief

Who should care

Organizations operating Siemens SINEMA Remote Connect Server for remote access to industrial control systems, particularly in critical infrastructure sectors. Security teams responsible for OT/ICS asset protection and backup management procedures.

Technical summary

The SINEMA Remote Connect Server application permits users to upload encrypted backup files. During the restoration process, the application fails to properly validate file paths within the backup archive. An attacker possessing the backup encryption key can craft a malicious backup containing files with directory traversal sequences (e.g., ../) that escape intended restoration directories. This path traversal weakness enables placement of executable files in sensitive locations, potentially achieving remote code execution on the server. The vulnerability requires network access and valid credentials/encryption key access, but no user interaction. CVSS 3.1 vector: AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:P/RL:O/RC:C.

Defensive priority

HIGH

Recommended defensive actions

• Apply vendor fix: Update SINEMA Remote Connect Server to V3.2 SP1 or later version
• Restrict access to backup encryption keys to authorized personnel only
• Monitor backup restoration activities for anomalous file paths
• Implement network segmentation for SINEMA Remote Connect Server deployments
• Review backup file integrity before restoration operations

Evidence notes

CISA ICS advisory ICSA-24-193-01 and Siemens SSA-381581 document this vulnerability with CVSS 8.8 (HIGH). The vulnerability exists in backup restoration functionality where path validation is insufficient.

Official resources