CVE-2025-3262: Transformers vulnerable to ReDoS attack through its SETTING_RE variable
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 SETTINGRE variable within the transformers/commands/chat.py file.
Published Jul 7, 2025 · Updated Aug 4, 2025
Affected packages
transformers
- Ecosystem
- PyPI
- Affected
- >= 4.49.0, < 4.51.0
- Fixed in
- 4.51.0
- Check
pip show transformers
Advisory details
From the GitHub Advisory Database (CC BY 4.0).
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.
References
- https://nvd.nist.gov/vuln/detail/CVE-2025-3262
- https://github.com/huggingface/transformers/commit/0720e206c6ba28887e4d60ef60a6a089f6c1cc76
- https://huntr.com/bounties/ecf5ccc4-39e7-4fb3-b547-14a41d31a184
- https://github.com/huggingface/transformers/commit/126abe3461762e5fc180e7e614391d1b4ab051ca
- https://github.com/advisories/GHSA-489j-g2vx-39wf
How this page is made: the data panel comes from the GitHub Advisory Database, CISA’s KEV catalog, the NVD and FIRST EPSS, and updates twice a day. No analysis has been written for this entry yet. Methodology
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