CVE-2026-34789
Description
A flaw was found in FreeCAD, a 3D parametric modeler. A remote attacker could exploit this vulnerability by tricking a user into opening a specially crafted FCStd document. When the document is restored, attacker-controlled module attributes are processed, leading to the execution of arbitrary Python code. This could result in a complete system compromise.
Statement
This Important vulnerability in FreeCAD allows for arbitrary code execution when a user opens a specially crafted FCStd document. While user interaction is required, the low attack complexity and potential for complete system compromise elevate the risk, making it more severe than a Moderate flaw.
Understanding the Weakness (CWE)
Integrity
Technical Impact: Modify Application Data; Unexpected State
Attackers can modify unexpected objects or data that was assumed to be safe from modification. Deserialized data or code could be modified without using the provided accessor functions, or unexpected functions could be invoked.
Availability
Technical Impact: DoS: Resource Consumption (CPU)
If a function is making an assumption on when to terminate, based on a sentry in a string, it could easily never terminate.
Other
Technical Impact: Varies by Context
The consequences can vary widely, because it depends on which objects or methods are being deserialized, and how they are used. Making an assumption that the code in the deserialized object is valid is dangerous and can enable exploitation. One example is attackers using gadget chains to perform unauthorized actions, such as generating a shell.
Frequently Asked Questions
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