Code execution via untrusted model deserialization
Published Dec 23, 2025 · Updated Dec 23, 2025
Deserialization in Transformer-XL model parsing in Hugging Face Transformers allows remote attackers to execute code through a crafted model file. The advisory identifies missing validation before untrusted model data is deserialized but does not disclose the parsing function, serialization format, or unsafe API. Exploitation requires the current user to open the file or visit a page that supplies it, and the resulting code runs with that user's privileges.
Summary
What happened
Deserialization in Transformer-XL model parsing in Hugging Face Transformers allows remote attackers to execute code through a crafted model file. The advisory identifies missing validation before untrusted model data is deserialized but does not disclose the parsing function, serialization format, or unsafe API. Exploitation requires the current user to open the file or visit a page that supplies it, and the resulting code runs with that user's privileges.
The record
- CVE
- CVE-2025-14921
- Published
- Dec 23, 2025
- Updated
- Dec 23, 2025
- Vendor
- Hugging Face
- Product
- Transformers
- Classifications
- CWE-502, T1204.002
- Attack vector
- local
- Privileges
- unauthenticated
Timeline
How it unfolded
- Dec 23, 2025CVE publishedPublication date reported by the CVE source.
- Dec 23, 2025Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
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- Affected versionversion=9c8bd3fc1befe54f3efb9f385561eef49f060a70
What conditions does exploitation require?
What is affected?
Published CVSS scores
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Attacks
What attackers are doing with it
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Weakness, pattern, technique
Public exploit references
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Technologies
Your stack
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Your stack
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