Deserialization of Untrusted Data Affecting transformers package, versions [0,5.0.0rc1)
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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- published24 Dec 2025
- disclosed23 Dec 2025
- creditPeter Girnus
Introduced: 23 Dec 2025
CVE-2025-14920 (opens in a new tab)How to fix?
Upgrade transformers to version 5.0.0rc1 or higher.
Overview
transformers is a State-of-the-art Machine Learning for JAX, PyTorch and TensorFlow
Affected versions of this package are vulnerable to Deserialization of Untrusted Data via the parsing of model files. An attacker can execute arbitrary code by tricking a user into opening a specially crafted model file.
Note:
The vendor closed the case as a duplicate of another report.
Details
Serialization is a process of converting an object into a sequence of bytes which can be persisted to a disk or database or can be sent through streams. The reverse process of creating object from sequence of bytes is called deserialization. Serialization is commonly used for communication (sharing objects between multiple hosts) and persistence (store the object state in a file or a database). It is an integral part of popular protocols like Remote Method Invocation (RMI), Java Management Extension (JMX), Java Messaging System (JMS), Action Message Format (AMF), Java Server Faces (JSF) ViewState, etc.
Deserialization of untrusted data (CWE-502) is when the application deserializes untrusted data without sufficiently verifying that the resulting data will be valid, thus allowing the attacker to control the state or the flow of the execution.