Vulnerability · Published Jul 7, 2025 · Assigned by @huntr_ai
CVE-2025-3262Regular Expression Denial of Service (ReDoS) in huggingface/transformers
Medium 5.3
In plain English
A medium-severity regular-expression denial of service in huggingface/transformers from huggingface. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.5% (higher than 43% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
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 packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| PyPI | transformers | 4.51.0 | GHSA-489j-g2vx-39wf |
| PyPI | transformers | 4.51.0 | PYSEC-2026-1979 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| huggingface | huggingface/transformers | unspecified – before 4.51.0 |
Weakness: CWE-1333 · Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L