CyberSecBulletin
CVE-2023-28489NVD status: Modified

CP-8031 MASTER MODULE: Improper Neutralization of Special Elements used in a Command

CVE-2023-28489 is a critical-severity improper neutralization of special elements used in a command vulnerability in CP-8031 MASTER MODULE from Siemens, with a CVSS 3.1 base score of 9.8 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. Affected CP-8031 MASTER MODULE versions: All versions < CPCI85 V05. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 2.84% chance of exploitation within 30 days, higher than 87% of scored CVEs.

Patch this week

Critical severity: a successful attack would have severe impact.

What to do

  1. Update Cp-8031 Firmware to cpci85_v05 or a later version.
  2. Update Cp-8050 Firmware to cpci85_v05 or a later version.
  3. Read the advisory on cert-portal.siemens.com for workarounds and exact fixed builds.
  4. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.

Affected products and versions

VendorProductAffected versionsFixed in
SiemensCP-8031 MASTER MODULEAll versions < CPCI85 V05Not stated
SiemensCP-8050 MASTER MODULEAll versions < CPCI85 V05Not stated
SiemensCp-8031 Firmwarebefore cpci85_v05cpci85_v05
SiemensCp-8050 Firmwarebefore cpci85_v05cpci85_v05

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
NoneNo account or login is needed.
User interaction
NoneNo action by a victim is required.
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:N/UI:N/S:U/C:H/I:H/A:H. Scored by NVD.

Scoring systemScoreSeverityScored by
CVSS 3.19.8CriticalCNA (siemens.com)
CVSS 3.19.8CriticalNVD

Official description

A vulnerability has been identified in CP-8031 MASTER MODULE (All versions < CPCI85 V05), CP-8050 MASTER MODULE (All versions < CPCI85 V05). Affected devices are vulnerable to command injection via the web server port 443/tcp, if the parameter “Remote Operation” is enabled. The parameter is disabled by default. The vulnerability could allow an unauthenticated remote attacker to perform arbitrary code execution on the device.

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 a Command

The product constructs all or part of a command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended command when 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.
  • If possible, ensure that all external commands called from the program are statically created.
  • Run time: Run time policy enforcement may be used in an allowlist fashion to prevent use of any non-sanctioned commands.

More Improper Neutralization of Special Elements used in a Command vulnerabilities (CWE-77)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: yes, technical impact: total).
  3. Record last changed materially (score, affected products, status or references).

References

Other vulnerabilities in CP-8031 MASTER MODULE

All CP-8031 MASTER MODULE vulnerabilities

Recent Improper Neutralization of Special Elements used in a Command vulnerabilities

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