Full Report
A vulnerability has been identified in the integrated S7-1500 CPU of SINUMERIK ONE and SINUMERIK MC products that could allow an attacker to cause a denial of service condition. In order to exploit the vulnerability, an attacker must have access to the affected devices on port 102/tcp. Siemens is preparing updates and recommends specific countermeasures for products where updates are not, or not yet available. Note: The affected integrated S7-1500 CPUs and related products are advised in [1]. [1] https://cert-portal.siemens.com/productcert/html/ssa-592380.html
Analysis Summary
# Vulnerability: Denial of Service in Integrated S7-1500 CPU (SINUMERIK ONE/MC)
## CVE Details
- CVE ID: CVE-2023-46156
- CVSS Score: 7.5 (High)
- CWE: CWE-416: Use After Free (Implied by vector details and analysis)
## Affected Systems
- Products: SINUMERIK MC, SINUMERIK ONE (which uses an integrated S7-1500 CPU)
- Versions:
- SINUMERIK MC: All versions < V1.24
- SINUMERIK ONE: All versions < V6.24
- Configurations: Requires network access to the affected devices on port 102/tcp.
## Vulnerability Description
The integrated S7-1500 CPU within the affected SINUMERIK products improperly handles specially crafted packets sent to TCP port 102. Successful exploitation can lead to a denial of service (DoS) condition, requiring a device restart to restore normal operations.
## Exploitation
- Status: Not explicitly stated if exploited in the wild, but a PoC is likely feasible given the CVSS vector details (Exploit Code Maturity (E) is set to 'P' - Proof-of-Concept).
- Complexity: Low (AV:N/AC:L/PR:N/UI:N)
- Attack Vector: Network
## Impact
- Confidentiality: No impact (N)
- Integrity: No impact (N)
- Availability: High impact (H) (Service disruption requiring restart)
## Remediation
### Patches
- SINUMERIK MC: Update to V1.24 or later version.
- SINUMERIK ONE: Update to V6.24 or later version.
*Note: Updated software versions must be obtained from Siemens customer support or a local partner.*
### Workarounds
1. **Network Segmentation:** Expose port 102/tcp of the integrated S7-1500 CPU only to trusted network environments.
2. Follow Siemens General Security Recommendations for operational guidelines.
## Detection
- **Indicators of Compromise:** System unavailability or unexpected restarts on affected devices. Monitoring for unexpected traffic patterns targeting port 102/tcp.
- **Detection Methods and Tools:** Network monitoring tools capable of inspecting traffic to port 102/tcp for anomalous or malformed packets targeting the S7 protocol stack.
## References
- Vendor Advisories: SSA-280603 (Specific reference [1] also points to SSA-592380 for a broader list of affected products)
- Relevant links:
- hxxps://cert-portal.siemens.com/productcert/html/ssa-592380.html
- hxxps://cert-portal.siemens.com/productcert/html/ssa-280603.html
- hxxps://www.siemens.com/cert/operational-guidelines-industrial-security
- hxxps://www.siemens.com/industrialsecurity