CVE-2025-6638

HIGH

Hugging Face Transformers < 4.53.0 - Regular Expression Denial of Service in MarianTokenizer

Title source: llm
STIX 2.1

Description

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.

Scores

CVSS v3 7.5
EPSS 0.0049
EPSS Percentile 37.9%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

CISA SSVC

Vulnrichment
Exploitation poc
Automatable yes
Technical Impact partial

Details

CWE
CWE-1333
Status published
Products (2)
huggingface/transformers 4.52.4
pypi/transformers 0 - 4.53.0PyPI
Published Sep 12, 2025
Tracked Since Feb 18, 2026