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.
References (2)
Core 2
Core References
Exploit, Third Party Advisory
https://huntr.com/bounties/ecf5ccc4-39e7-4fb3-b547-14a41d31a184
Scores
CVSS v3
7.5
EPSS
0.0043
EPSS Percentile
34.1%
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
< 4.51.0
pypi/transformers
4.49.0 - 4.51.0PyPI
Published
Jul 07, 2025
Tracked Since
Feb 18, 2026