CVE Vulnerabilities

CVE-2025-40759

Deserialization of Untrusted Data

Published: Aug 12, 2025 | Modified: Aug 12, 2025
CVSS 3.x
N/A
Source:
NVD
CVSS 2.x
RedHat/V2
RedHat/V3
Ubuntu

A vulnerability has been identified in SIMATIC S7-PLCSIM V17 (All versions), SIMATIC STEP 7 V17 (All versions), SIMATIC STEP 7 V18 (All versions), SIMATIC STEP 7 V19 (All versions < V19 Update 4), SIMATIC STEP 7 V20 (All versions), SIMATIC WinCC V17 (All versions), SIMATIC WinCC V18 (All versions), SIMATIC WinCC V19 (All versions < V19 Update 4), SIMATIC WinCC V20 (All versions), 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), SIMOTION SCOUT TIA V5.5 (All versions), SIMOTION SCOUT TIA V5.6 (All versions < V5.6 SP1 HF7), SIMOTION SCOUT TIA V5.7 (All versions), 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), TIA Portal Cloud V18 (All versions), TIA Portal Cloud V19 (All versions < V5.2.1.1), TIA Portal Cloud V20 (All versions). Affected products do not properly sanitize stored security properties when parsing project files. This could allow an attacker to cause a type confusion and execute arbitrary code within the affected application.

Weakness

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

Extended Description

It is often convenient to serialize objects for communication or to save them for later use. However, deserialized data or code can often be modified without using the provided accessor functions if it does not use cryptography to protect itself. Furthermore, any cryptography would still be client-side security – which is a dangerous security assumption. Data that is untrusted can not be trusted to be well-formed. When developers place no restrictions on “gadget chains,” or series of instances and method invocations that can self-execute during the deserialization process (i.e., before the object is returned to the caller), it is sometimes possible for attackers to leverage them to perform unauthorized actions, like generating a shell.

Potential Mitigations

  • Make fields transient to protect them from deserialization.
  • An attempt to serialize and then deserialize a class containing transient fields will result in NULLs where the transient data should be. This is an excellent way to prevent time, environment-based, or sensitive variables from being carried over and used improperly.

References