CyberSecBulletin
CVE-2022-40176NVD status: Modified

Desigo PXM30-1: Improper Neutralization of Special Elements used in an OS Command

Published Updated By the CyberSecBulletin desk

CVE-2022-40176 is a high-severity improper neutralization of special elements used in an OS command vulnerability in Desigo PXM30-1 from Siemens, with a CVSS 3.1 base score of 8.0 out of 10. It can be exploited remotely over the network by an attacker with a low-privileged account, but only if a user takes part, for example by opening a link or file. Affected Desigo PXM30-1 versions: All versions < V02.20.126.11-41. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 1.37% chance of exploitation within 30 days, higher than 72% of scored CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update Desigo Pxm30-1 Firmware to 02.20.126.11-41 or a later version.
  2. Update Desigo Pxm30.e Firmware to 02.20.126.11-41 or a later version.
  3. Update Desigo Pxm40-1 Firmware to 02.20.126.11-41 or a later version.
  4. Read the advisory on cert-portal.siemens.com for workarounds and exact fixed builds.
  5. Because the attack needs a user to take part, warn users about unexpected links and files related to this product until it is patched.

Affected products and versions

VendorProductAffected versionsFixed in
SiemensDesigo PXM30-1All versions < V02.20.126.11-41Not stated
SiemensDesigo PXM30.EAll versions < V02.20.126.11-41Not stated
SiemensDesigo PXM40-1All versions < V02.20.126.11-41Not stated
SiemensDesigo PXM40.EAll versions < V02.20.126.11-41Not stated
SiemensDesigo PXM50-1All versions < V02.20.126.11-41Not stated
SiemensDesigo PXM50.EAll versions < V02.20.126.11-41Not stated
SiemensPXG3.W100-1All versions < V02.20.126.11-37Not stated
SiemensPXG3.W100-2All versions < V02.20.126.11-41Not stated
SiemensPXG3.W200-1All versions < V02.20.126.11-37Not stated
SiemensPXG3.W200-2All versions < V02.20.126.11-41Not stated
SiemensDesigo Pxm30-1 Firmwarebefore 02.20.126.11-4102.20.126.11-41
SiemensDesigo Pxm30.e Firmwarebefore 02.20.126.11-4102.20.126.11-41
SiemensDesigo Pxm40-1 Firmwarebefore 02.20.126.11-4102.20.126.11-41
SiemensDesigo Pxm40.e Firmwarebefore 02.20.126.11-4102.20.126.11-41
SiemensDesigo Pxm50-1 Firmwarebefore 02.20.126.11-4102.20.126.11-41
SiemensDesigo Pxm50.e Firmwarebefore 02.20.126.11-4102.20.126.11-41
SiemensPxg3.w100-1 Firmwarebefore 02.20.126.11-3702.20.126.11-37
SiemensPxg3.w100-2 Firmwarebefore 02.20.126.11-4102.20.126.11-41
SiemensPxg3.w200-1 Firmwarebefore 02.20.126.11-3702.20.126.11-37
SiemensPxg3.w200-2 Firmwarebefore 02.20.126.11-4102.20.126.11-41

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
LowA basic user account is enough.
User interaction
RequiredA user must take an action such as opening a file or link.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H. Scored by NVD.

Official description

A vulnerability has been identified in Desigo PXM30-1 (All versions < V02.20.126.11-41), Desigo PXM30.E (All versions < V02.20.126.11-41), Desigo PXM40-1 (All versions < V02.20.126.11-41), Desigo PXM40.E (All versions < V02.20.126.11-41), Desigo PXM50-1 (All versions < V02.20.126.11-41), Desigo PXM50.E (All versions < V02.20.126.11-41), PXG3.W100-1 (All versions < V02.20.126.11-37), PXG3.W100-2 (All versions < V02.20.126.11-41), PXG3.W200-1 (All versions < V02.20.126.11-37), PXG3.W200-2 (All versions < V02.20.126.11-41). There exists an Improper Neutralization of Special Elements used in an OS Command with root privileges during a restore operation due to the missing validation of the names of files included in the input package. By restoring a specifically crafted package, a remote low-privileged attacker can execute arbitrary system commands with root privileges on the device, leading to a full compromise.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Improper Neutralization of Special Elements used in an OS Command

The product constructs all or part of an OS command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended OS command before it is sent to a downstream component.

How developers prevent this class of flaw

  • If at all possible, use library calls rather than external processes to recreate the desired functionality.
  • For any data that will be used to generate a command to be executed, keep as much of that data out of external control as possible. For example, in web applications, this may require storing the data locally in the session's state instead of sending it out to the client in a hidden form field.
  • For any security checks that are performed on the client side, ensure that these checks are duplicated on the server side, in order to avoid CWE-602. Attackers can bypass the client-side checks by modifying values after the checks have been performed, or by changing the client to remove the client-side checks entirely. Then, these modified values would be submitted to the server.

More Improper Neutralization of Special Elements used in an OS Command vulnerabilities (CWE-78)

Timeline

  1. CVE record published.
  2. Record last changed materially (score, affected products, status or references).

References

Other vulnerabilities in Desigo PXM30-1

All Desigo PXM30-1 vulnerabilities

Recent Improper Neutralization of Special Elements used in an OS Command vulnerabilities

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