TransformersGHSA-489j-g2vx-39wf
Transformers vulnerable to ReDoS attack through its SETTING_RE variable
Fix: upgrade to 4.51.0 or later
A Regular Expression Denial of Service (ReDoS) vulnerability was discovered in the huggingface/transformers repository, specifically in version 4.49.0. The vulnerability is due to inefficient regular expression complexity in the SETTING_RE variable within the transformers/commands/chat.py file. The regex contains repetition groups and non-optimized quantifiers, leading to exponential backtracking when processing 'almost matching' payloads. This can degrade application performance and potentially result in a denial-of-service (DoS) when handling specially crafted input strings. The issue is fixed in version 4.51.0.
Affected versions
| Package | Affected | Fixed in |
|---|---|---|
| transformers PyPI | >= 4.49.0, < 4.51.0 | 4.51.0 |
Details and references
- CVSS 3.1
- CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
- Severity from
- GitHub (reviewed advisory)
- Weakness
- CWE-1333
- Also known as
- CVE-2025-3262, PYSEC-2026-1979