A vulnerability has been identified in SIMATIC CP 1242-7 V2 (All versions < V3.3.46), SIMATIC CP 1243-1 (All versions < V3.3.46), SIMATIC CP 1243-7 LTE EU (All versions < V3.3.46), SIMATIC CP 1243-7 LTE US (All versions < V3.3.46), SIMATIC CP 1243-8 IRC (All versions < V3.3.46), SIMATIC CP 1542SP-1 IRC (All versions >= V2.0 < V2.2.28), SIMATIC CP 1543-1 (All versions < V3.0.22), SIMATIC CP 1543SP-1 (All versions >= V2.0 < V2.2.28), SIPLUS ET 200SP CP 1542SP-1 IRC TX RAIL (All versions >= V2.0 < V2.2.28), SIPLUS ET 200SP CP 1543SP-1 ISEC (All versions >= V2.0 < V2.2.28), SIPLUS ET 200SP CP 1543SP-1 ISEC TX RAIL (All versions >= V2.0 < V2.2.28), SIPLUS NET CP 1242-7 V2 (All versions < V3.3.46), SIPLUS NET CP 1543-1 (All versions < V3.0.22), SIPLUS S7-1200 CP 1243-1 (All versions < V3.3.46), SIPLUS S7-1200 CP 1243-1 RAIL (All versions < V3.3.46). The application lacks proper validation of user-supplied data when parsing specific messages. This could result in a heap-based buffer overflow. An attacker could leverage this vulnerability to execute code in the context of device.
Weakness
A heap overflow condition is a buffer overflow, where the buffer that can be overwritten is allocated in the heap portion of memory, generally meaning that the buffer was allocated using a routine such as malloc().
Affected Software
| Name |
Vendor |
Start Version |
End Version |
| Simatic_cp_1242-7_v2_firmware |
Siemens |
* |
* |
Potential Mitigations
- Use automatic buffer overflow detection mechanisms that are offered by certain compilers or compiler extensions. Examples include: the Microsoft Visual Studio /GS flag, Fedora/Red Hat FORTIFY_SOURCE GCC flag, StackGuard, and ProPolice, which provide various mechanisms including canary-based detection and range/index checking.
- D3-SFCV (Stack Frame Canary Validation) from D3FEND [REF-1334] discusses canary-based detection in detail.
- Run or compile the software using features or extensions that randomly arrange the positions of a program’s executable and libraries in memory. Because this makes the addresses unpredictable, it can prevent an attacker from reliably jumping to exploitable code.
- Examples include Address Space Layout Randomization (ASLR) [REF-58] [REF-60] and Position-Independent Executables (PIE) [REF-64]. Imported modules may be similarly realigned if their default memory addresses conflict with other modules, in a process known as “rebasing” (for Windows) and “prelinking” (for Linux) [REF-1332] using randomly generated addresses. ASLR for libraries cannot be used in conjunction with prelink since it would require relocating the libraries at run-time, defeating the whole purpose of prelinking.
- For more information on these techniques see D3-SAOR (Segment Address Offset Randomization) from D3FEND [REF-1335].
References