CVE-2025-3933: Regular Expression Denial of Service (ReDoS) in huggingface/transformers

Severity: medium (CVSS 5.3 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.5% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2025-07-11 · updated 2026-06-17
Weakness: CWE-1333

Description

A Regular Expression Denial of Service (ReDoS) vulnerability was discovered in the Hugging Face Transformers library, specifically within the DonutProcessor class's `token2json()` method. This vulnerability affects versions 4.50.3 and earlier, and is fixed in version 4.52.1. The issue arises from the regex pattern `<s_(.*?)>` which can be exploited to cause excessive CPU consumption through crafted input strings due to catastrophic backtracking. This vulnerability can lead to service disruption, resource exhaustion, and potential API service vulnerabilities, impacting document processing tasks using the Donut model.

Affected products

huggingface/transformers: before 4.52.1 — fixed in 4.52.1

How to fix

Upgrade to a fixed version: huggingface/transformers 4.52.1. Check the vendor advisory for mitigations.

References

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