CVE-2025-2099

What it is

A vulnerability in the `preprocess_string()` function of the `transformers.testing_utils` module in huggingface/transformers version v4.48.3 allows for a Regular Expression Denial of Service (ReDoS) attack. The regular expression used to process code blocks in docstrings contains nested quantifiers, leading to exponential backtracking when processing input with a large number of newline characters. An attacker can exploit this by providing a specially crafted payload, causing high CPU usage and potential application downtime, effectively resulting in a Denial of Service (DoS) scenario.

At a glance

Exploitability

Can be exploited over the network without logging in. High risk of service disruption.

Exploit odds

0.6% chance of exploitation in the next 30 days (EPSS).

Fix

A patch, advisory or fixed version is referenced. Upgrade or apply it.

Timeline

1. 2025-05-19 12:15 UTC PublishedDisclosed publicly on CVE.org and NVD
2. 2026-06-17 09:06 UTC Last updatedMost recent change to the record

Details

Published

2025-05-19 12:15 UTC

Last modified

2026-06-17 09:06 UTC

Exploit probability

0.6% · EPSS, next 30 days

Weakness

CWE-1333

Record status

Analyzed

Affected

• Huggingface Transformers ≤ 4.48.3

Attack profile CVSS 3.1 · 7.5

Attack vector

Network

Complexity

Low

Privileges needed

None

User interaction

None

Scope

Unchanged

Confidentiality

None

Integrity

None

Availability

High