CVE-2024-12720: Regular Expression Denial of Service (ReDoS) in huggingface/transformers

Severity: high (CVSS 7.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.7% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2025-03-20 · updated 2026-06-17
Weakness: CWE-1333

Description

A Regular Expression Denial of Service (ReDoS) vulnerability was identified in the huggingface/transformers library, specifically in the file tokenization_nougat_fast.py. The vulnerability occurs in the post_process_single() function, where a regular expression processes specially crafted input. The issue stems from the regex exhibiting exponential time complexity under certain conditions, leading to excessive backtracking. This can result in significantly high CPU usage and potential application downtime, effectively creating a Denial of Service (DoS) scenario. The affected version is v4.46.3 (latest).

Affected products

huggingface/transformers: before 4.48.0 — fixed in 4.48.0

How to fix

Upgrade to a fixed version: huggingface/transformers 4.48.0. Check the vendor advisory for mitigations.

References

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