CVE-2025-14921 Hugging Face Transformers Transformer-XL Model Deserialization of Untrusted Data Remote Code Execution Vulnerability
Remote attackers can execute arbitrary code by tricking users into opening malicious model files in Hugging Face Transformers.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- A user has to click or open something
- Fix
- None listed
What is CVE-2025-14921?
CVE-2025-14921 is a high-severity unsafe deserialization vulnerability in Hugging Face Transformers, published on 23 Dec 2025. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.
Official description
Hugging Face Transformers Transformer-XL Model Deserialization of Untrusted Data Remote Code Execution Vulnerability. This vulnerability allows remote attackers to execute arbitrary code on affected installations of Hugging Face Transformers. User interaction is required to exploit this vulnerability in that the target must visit a malicious page or open a malicious file.
The specific flaw exists within the parsing of model files. The issue results from the lack of proper validation of user-supplied data, which can result in deserialization of untrusted data. An attacker can leverage this vulnerability to execute code in the context of the current user. Was ZDI-CAN-25424.
Weakness: CWE-502
Which versions are affected by CVE-2025-14921?
1 open source package ship an affected version, including transformers. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
transformers PyPI | All versions to 4.54.1 | None |
Products include Huggingface Transformers.
How do I fix CVE-2025-14921?
No fix has been published for CVE-2025-14921 yet. Limit exposure of the affected software until one is available.
Upgrade, and only deserialise data from trusted sources or with an allow-list of types. More about Unsafe deserialization.
Is CVE-2025-14921 being exploited?
There is no known exploitation of CVE-2025-14921 in the wild and no public exploit code.
Other vulnerabilities in Hugging Face Transformers
- CVE-2023-7018 Deserialization of Untrusted Data in huggingface/transformers
- CVE-2023-6730 Deserialization of Untrusted Data in huggingface/transformers
- CVE-2024-11393 Hugging Face Transformers MaskFormer Model Deserialization of Untrusted Data Remote Code Execution Vulnerability
- CVE-2024-11394 Hugging Face Transformers Trax Model Deserialization of Untrusted Data Remote Code Execution Vulnerability
- CVE-2026-5241 Policy Bypass in LightGlue Nested Config Resolution in huggingface/transformers
Sources
Also known as GHSA-hv5j-58mm-f6v9, PYSEC-2025-212.