Full Report
Multiple vulnerabilities have been identified in the additional GNU/Linux subsystem of the SIMATIC S7-1500 TM MFP V1.0. Siemens has released a new version for SIMATIC S7-1500 TM MFP - GNU/Linux subsystem and recommends to update to the latest version. This advisory lists vulnerabilities for firmware version V1.0 only; for V1.1 refer to Siemens Security Advisory SSA-265688 (https://cert-portal.siemens.com/productcert/html/ssa-265688.html).
Analysis Summary
# Vulnerability: Multiple Linux Kernel Vulnerabilities in SIMATIC S7-1500 TM MFP (Firmware V1.0)
## CVE Details
This advisory bundles multiple Linux kernel vulnerabilities. The highest severity score listed in the initial advisory text is **9.8 (CVSS v3.1)**, correlating to **CVE-2022-41674** (CVSS v3.1: 8.1). However, the main context suggests a collection of flaws inherited from the underlying kernel components.
* **CVE ID:** CVE-2022-39188, CVE-2022-39190, CVE-2022-40307, CVE-2022-40768, CVE-2022-41218, CVE-2022-41222, CVE-2022-41674, CVE-2022-41849, CVE-2022-41850, CVE-2022-42328, CVE-2022-42329, and many others added in subsequent updates (e.g., CVE-2021-44879, CVE-2024-25062 are mentioned in history).
* **CVSS Score:** Scores vary widely, up to 9.8 (CVSS v3.1, likely associated with the initial main finding, though not explicitly mapped to a specific CVE within the provided snippet) and 8.1 for CVE-2022-41674.
* **CWE:** Varies (e.g., CWE-20: Improper Input Validation, CWE-362: Race Condition, CWE-416: Use After Free, CWE-667: Improper Locking).
## Affected Systems
* **Products:** SIMATIC S7-1500 TM MFP - GNU/Linux subsystem.
* **Versions:** Firmware Version V1.0 only. (Note: For V1.1, refer to SSA-265688).
* **Configurations:** Inherent to the described firmware version. All vulnerabilities are based on the underlying Linux kernel versions shipped in V1.0.
## Vulnerability Description
Multiple vulnerabilities stem from flaws within the additional GNU/Linux subsystem used by the affected product. These flaws originate from known issues in the upstream Linux kernel, including:
1. **Race Conditions (e.g., CVE-2022-39188, CVE-2022-40307, CVE-2022-41849, CVE-2022-41850):** Risks of memory corruption (Use-After-Free) due to unprotected concurrent access to kernel resources, especially involving TLB handling, device drivers, or suspend/resume operations.
2. **Use-After-Free (UAF) (e.g., CVE-2022-41218, CVE-2022-41222):** Errors where the system attempts to use memory after it has already been released, potentially leading to crashes or arbitrary code execution under certain conditions.
3. **Improper Input/Resource Handling (e.g., CVE-2022-41674, CVE-2022-39190, CVE-2022-40768):** Flaws like buffer overflows (WLAN frames), uncontrolled resource consumption, or exposure of sensitive kernel memory due to lack of sanitization or proper locking.
4. **Deadlock (CVE-2022-42328, CVE-2022-42329):** Issues in the netback driver that can cause the system to become unresponsive under specific network packet dropping scenarios.
## Exploitation
* **Status:** The advisory indicates that many of the underlying CVEs had existing Proof-of-Concept (PoC) material ("E:P" in CVSS vectors implies exploitability in the field or existence of Proof-of-Concept code). Specific exploitation status within the SIMATIC context is not detailed, but the underlying flaws are known to be exploitable.
* **Complexity:** Varies by specific CVE, ranging from Local (AV:L) to Adjacent Network (AV:A). Several require Local access (PR:L) or specific timing/conditions.
* **Attack Vector:** Primarily Local (L) or Adjacent Network (A) depending on the specific flaw (e.g., network frame injection).
## Impact
The impact varies based on the specific vulnerability exploited:
* **Confidentiality (C):** Ranges from None (N) to High (H) (e.g., CVE-2022-40768 allows exposure of sensitive kernel memory).
* **Integrity (I):** Ranges from None (N) to High (H) (e.g., UAFs or Buffer Overflows can lead to integrity compromise).
* **Availability (A):** Several vulnerabilities carry High (H) impact on Availability, primarily relating to Denial of Service (DoS) or system crashes caused by race conditions or deadlocks.
## Remediation
### Patches
* Siemens **recommends updating to the latest version** of the SIMATIC S7-1500 TM MFP - GNU/Linux subsystem.
* The advisory specifically covers **V1.0**. Users must upgrade beyond V1.0 to address these issues.
* **Note:** This advisory (SSA-794697) is **no longer maintained**. Users should follow the remediation path outlined in the most current advisories related to this product line, specifically referencing **SSA-265688** for version V1.1 and subsequent updates.
### Workarounds
No specific workarounds are detailed in the provided summary text for these kernel vulnerabilities. Patching is the directive.
## Detection
* **Indicators of Compromise:** Detection would rely on identifying the specific low-level system calls or memory corruption patterns associated with the underlying Linux kernel vulnerabilities (e.g., unexpected kernel panics, memory access violations, or unexplained service instability).
* **Detection Methods and Tools:** Standard system logging (syslog, kernel dumps enabled) may capture evidence of crashes related to UAF or deadlock situations. Deep analysis would require monitoring low-level kernel activity, which is often inaccessible in protected industrial environments.
## References
* **Vendor Advisories:**
* SSA-794697 (Initial advisory reference)
* SSA-265688 (Reference for firmware V1.1 and newer)
* **Relevant Links (Defanged):**
* cert-portal-siemens-com/productcert/html/ssa-265688-html (For V1.1 remediation)
* siemens-com/cert/advisories (General Siemens CERT contact)