Vulnerability in Huggingface Huggingface/transformers

CVE-2025-6638

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…

Vulnerability class: ReDoS (Regular Expression Denial of Service)

EPSS: 0.005 (38.0th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2025-6638?
CVE-2025-6638 is a high-severity vulnerability in Huggingface Huggingface/transformers, classified under Inefficient Regular Expression Complexity. CVSS score: 7.5/10. Published 2025-09-12.
How severe is CVE-2025-6638?
High severity. CVSS v3 base score is 7.5 out of 10.
Is CVE-2025-6638 known to be exploited?
1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.