VulnWatch VulnWatch
← Back to dashboard
Low osv · PYSEC-2026-1979

Transformers vulnerable to ReDoS attack through its SETTING_RE variable

Published Jul 7, 2026 CVSS 3.1

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 AI Products

transformers
Get the weekly digest. Every Monday: top AI security stories of the week. Free.