Deserialization of Untrusted Data Affecting pyfory package, versions [,0.12.3)
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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- published1 Oct 2025
- disclosed1 Oct 2025
- creditMapta
Introduced: 1 Oct 2025
NewCVE-2025-61622 (opens in a new tab)How to fix?
Upgrade pyfory to version 0.12.3 or higher.
Overview
pyfory is an Apache Fory™ is a blazingly fast multi-language serialization framework powered by jit and zero-copy
Affected versions of this package are vulnerable to Deserialization of Untrusted Data via the pickle module. An attacker can execute arbitrary code by crafting a data stream that triggers the pickle-fallback serializer during deserialization.
Note:
This is only exploitable if the application reads serialized data from untrusted sources.
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.