CVE Vulnerabilities

CVE-2020-7586

Heap-based Buffer Overflow

Published: Jun 10, 2020 | Modified: Apr 22, 2021
CVSS 3.x
7.8
HIGH
Source:
NVD
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
CVSS 2.x
4.6 MEDIUM
AV:L/AC:L/Au:N/C:P/I:P/A:P
RedHat/V2
RedHat/V3
Ubuntu

A vulnerability has been identified in SIMATIC PCS 7 V8.2 and earlier (All versions), SIMATIC PCS 7 V9.0 (All versions < V9.0 SP3), SIMATIC PDM (All versions < V9.2), SIMATIC STEP 7 V5.X (All versions < V5.6 SP2 HF3), SINAMICS STARTER (containing STEP 7 OEM version) (All versions < V5.4 HF2). A buffer overflow vulnerability could allow a local attacker to cause a Denial-of-Service situation. The security vulnerability could be exploited by an attacker with local access to the affected systems. Successful exploitation requires user privileges but no user interaction. The vulnerability could allow an attacker to compromise the availability of the system as well as to have access to confidential information.

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_pcs_7 Siemens * *
Simatic_process_device_manager Siemens * *
Simatic_step_7 Siemens * 5.6 (excluding)
Simatic_step_7 Siemens 5.6 (including) 5.6 (including)
Simatic_step_7 Siemens 5.6-sp1 (including) 5.6-sp1 (including)
Simatic_step_7 Siemens 5.6-sp2 (including) 5.6-sp2 (including)
Simatic_step_7 Siemens 5.6-sp2_hotfix1 (including) 5.6-sp2_hotfix1 (including)
Sinamics_starter Siemens * 5.4 (excluding)
Sinamics_starter Siemens 5.4 (including) 5.4 (including)

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