AI and data stack advisories

Severe, 6 weeks1496Projects326

1496 severe, 6 weeks · 326 projects

TransformersGHSA-59p9-h35m-wg4g

Hugging Face Transformers is vulnerable to ReDoS through its MarianTokenizer

Transformers

CVE-2025-6638 · Published Sep 12, 2025 · updated Sep 10, 2026

Medium5.3
Fix: upgrade to 4.53.0 or later
GitHub advisory

A Regular Expression Denial of Service (ReDoS) vulnerability was discovered in the Hugging Face Transformers library, specifically affecting the MarianTokenizer's remove_language_code() method. This vulnerability is present in version 4.52.4 and has been fixed in version 4.53.0. The issue arises from inefficient regex processing, which can be exploited by crafted input strings containing malformed language code patterns, leading to excessive CPU consumption and potential denial of service.

Affected versions

PackageAffectedFixed in
transformers
PyPI
< 4.53.04.53.0
Details and references

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