CVE-2023-48363

Vulnerability

The RPC (Remote Procedure Call) communication protocol implementation in multiple Siemens industrial products does not properly handle certain unorganized RPC messages. This vulnerability affects OpenPCS 7 V9.1 (all versions < V9.1 SP2 UC05), SIMATIC BATCH V9.1 (all versions < V9.1 SP2 UC05), SIMATIC PCS 7 V9.1 (all versions < V9.1 SP2 UC05), SIMATIC Route Control V9.1 (all versions < V9.1 SP2 UC05), SIMATIC WinCC Runtime Professional V18 (all versions < V18 Update 4), SIMATIC WinCC Runtime Professional V19 (all versions < V19 Update 2), SIMATIC WinCC V7.4 (all versions), SIMATIC WinCC V7.5 (all versions < V7.5 SP2 Update 15), and SIMATIC WinCC V8.0 (all versions < V8.0 Update 4). The flaw resides in the RPC server's message parsing logic, which fails to gracefully handle malformed or unorganized RPC messages [1].

Exploitation

An attacker can exploit this vulnerability by sending specially crafted, unorganized RPC messages to the affected RPC server over the network. No authentication or user interaction is required. The attacker only needs network access to the target system's RPC endpoint. The malformed messages trigger an error condition in the RPC server that leads to a denial of service [1].

Impact

Successful exploitation causes a denial of service condition in the RPC server, making it unavailable. This can disrupt communication between components in the affected industrial automation systems, potentially halting process control operations. The vulnerability does not lead to arbitrary code execution or information disclosure [1].

Mitigation

Siemens has released fixes for most affected products. For SIMATIC WinCC Runtime Professional V18, apply Update 4; for V19, apply Update 2. For SIMATIC WinCC V7.5, apply V7.5 SP2 Update 15; for V8.0, apply V8.0 Update 4. For OpenPCS 7 V9.1, SIMATIC BATCH V9.1, SIMATIC PCS 7 V9.1, and SIMATIC Route Control V9.1, apply V9.1 SP2 UC05. SIMATIC WinCC V7.4 remains affected with no fix available as of the latest advisory update. Users should apply the appropriate updates or contact Siemens support for mitigation guidance [1].