CyberSecBulletin
CVE-2024-54678NVD status: Deferred

SIMATIC PCS neo V4.1: Deserialization of Untrusted Data

Published Updated By the CyberSecBulletin desk

CVE-2024-54678 is a high-severity deserialization of untrusted data vulnerability in SIMATIC PCS neo V4.1 from Siemens, with a CVSS 3.1 base score of 8.2 out of 10. It can be exploited with local access to the system by an attacker with a low-privileged account, but only if a user takes part, for example by opening a link or file. Affected SIMATIC PCS neo V4.1 versions: all versions. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.2% chance of exploitation within 30 days, which is low compared with other CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update SIMATIC PCS neo V6.0 to V6.0 SP1 Update 1 or a later version.
  2. Update SIMATIC STEP 7 V17 to V17 Update 9 or a later version.
  3. Update SIMATIC STEP 7 V18 to V18 Update 6 or a later version.
  4. 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
SiemensSIMATIC PCS neo V4.1all versionsNot stated
SiemensSIMATIC PCS neo V5.0all versionsNot stated
SiemensSIMATIC PCS neo V6.0before V6.0 SP1 Update 1V6.0 SP1 Update 1
SiemensSIMATIC S7-PLCSIM V17all versionsNot stated
SiemensSIMATIC STEP 7 V17before V17 Update 9V17 Update 9
SiemensSIMATIC STEP 7 V18before V18 Update 6V18 Update 6
SiemensSIMATIC STEP 7 V19before V19 Update 4V19 Update 4
SiemensSIMATIC STEP 7 V20before V20 Update 4V20 Update 4
SiemensSIMATIC WinCC V17before V17 Update 9V17 Update 9
SiemensSIMATIC WinCC V18before V18 Update 6V18 Update 6
SiemensSIMATIC WinCC V19before V19 Update 4V19 Update 4
SiemensSIMATIC WinCC V20before V20 Update 4V20 Update 4
SiemensSIMOCODE ES V17all versionsNot stated
SiemensSIMOCODE ES V18all versionsNot stated
SiemensSIMOCODE ES V19all versionsNot stated
SiemensSIMOCODE ES V20all versionsNot stated
SiemensSIMOTION SCOUT TIA V5.4before V17 Update 9V17 Update 9
SiemensSIMOTION SCOUT TIA V5.5before V18 Update 6V18 Update 6
SiemensSIMOTION SCOUT TIA V5.6before V19 Update 4V19 Update 4
SiemensSIMOTION SCOUT TIA V5.7before V20 Update 4V20 Update 4
SiemensSINAMICS Startdrive V17all versionsNot stated
SiemensSINAMICS Startdrive V18all versionsNot stated
SiemensSINAMICS Startdrive V19all versionsNot stated
SiemensSINAMICS Startdrive V20all versionsNot stated
SiemensSIRIUS Safety ES V17 (TIA Portal)all versionsNot stated

Version data comes from the organisation that assigned the CVE; 12 further products are omitted here. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
LocalThe attacker needs local access or must trick a user into running something.
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
ChangedThe attack can reach beyond the vulnerable component into other systems.
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:L/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:H. Scored by CNA (siemens.com).

Scoring systemScoreSeverityScored by
CVSS 4.08.6HighCNA (siemens.com)
CVSS 3.18.2HighCNA (siemens.com)

Official description

A vulnerability has been identified in SIMATIC PCS neo V4.1 (All versions), SIMATIC PCS neo V5.0 (All versions), SIMATIC PCS neo V6.0 (All versions < V6.0 SP1 Update 1), SIMATIC S7-PLCSIM V17 (All versions), SIMATIC STEP 7 V17 (All versions < V17 Update 9), SIMATIC STEP 7 V18 (All versions < V18 Update 6), SIMATIC STEP 7 V19 (All versions < V19 Update 4), SIMATIC STEP 7 V20 (All versions < V20 Update 4), SIMATIC WinCC V17 (All versions < V17 Update 9), SIMATIC WinCC V18 (All versions < V18 Update 6), SIMATIC WinCC V19 (All versions < V19 Update 4), SIMATIC WinCC V20 (All versions < V20 Update 4), SIMOCODE ES V17 (All versions), SIMOCODE ES V18 (All versions), SIMOCODE ES V19 (All versions), SIMOCODE ES V20 (All versions), SIMOTION SCOUT TIA V5.4 (All versions < V17 Update 9), SIMOTION SCOUT TIA V5.5 (All versions < V18 Update 6), SIMOTION SCOUT TIA V5.6 (All versions < V19 Update 4), SIMOTION SCOUT TIA V5.7 (All versions < V20 Update 4), SINAMICS Startdrive V17 (All versions), SINAMICS Startdrive V18 (All versions), SINAMICS Startdrive V19 (All versions), SINAMICS Startdrive V20 (All versions), SIRIUS Safety ES V17 (TIA Portal) (All versions), SIRIUS Safety ES V18 (TIA Portal) (All versions), SIRIUS Safety ES V19 (TIA Portal) (All versions), SIRIUS Safety ES V20 (TIA Portal) (All versions), SIRIUS Soft Starter ES V17 (TIA Portal) (All versions), SIRIUS Soft Starter ES V18 (TIA Portal) (All versions), SIRIUS Soft Starter ES V19 (TIA Portal) (All versions), SIRIUS Soft Starter ES V20 (TIA Portal) (All versions), TIA Portal Cloud V17 (All versions < V6.0.0.0), TIA Portal Cloud V18 (All versions < V6.3.0.2), TIA Portal Cloud V19 (All versions < V5.2.1.1), TIA Portal Cloud V20 (All versions < V5.2.2.2), TIA Portal Test Suite V20 (All versions < V20 Update 4). Affected products do not properly sanitize Interprocess Communication input received through a Windows Named Pipe accessible to all local users. This could allow an authenticated local attacker to cause a type confusion and execute arbitrary code within the affected application.

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

The underlying weakness: Deserialization of Untrusted Data

The product deserializes untrusted data without sufficiently ensuring that the resulting data will be valid.

How developers prevent this class of flaw

  • If available, use the signing/sealing features of the programming language to assure that deserialized data has not been tainted. For example, a hash-based message authentication code (HMAC) could be used to ensure that data has not been modified.
  • When deserializing data, populate a new object rather than just deserializing. The result is that the data flows through safe input validation and that the functions are safe.
  • Explicitly define a final object() to prevent deserialization.

More Deserialization of Untrusted Data vulnerabilities (CWE-502)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
  3. Record last changed materially (score, affected products, status or references).

References

Other vulnerabilities in SIMATIC PCS neo V4.1

All SIMATIC PCS neo V4.1 vulnerabilities

Recent Deserialization of Untrusted Data vulnerabilities

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