Vulnerability in Huggingface Huggingface/transformers
CVE-2025-2099
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.
Vulnerability class: ReDoS (Regular Expression Denial of Service)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.
EPSS exploit prediction
EPSS: 0.006 (45.6th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 46th percentile — 45.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.006 · newest: 0.006 · change: 0.000
Affected products
- Huggingface Huggingface/transformers — versions unspecified
- Huggingface Transformers
Weakness classification (CWE)
Public proof-of-concept exploits
References
- huntr.com/bounties/97b780f3-ffca-424f-ad5d-0e1c57a5bde4 (Exploit, Third Party Advisory)
- github.com/huggingface/transformers/commit/8cb522b4190bd556ce51be04942720650b1a… (Patch)
Frequently asked questions
- What is CVE-2025-2099?
- CVE-2025-2099 is a high-severity vulnerability in Huggingface Huggingface/transformers, classified under Inefficient Regular Expression Complexity. CVSS score: 7.5/10. Published 2025-05-19.
- How severe is CVE-2025-2099?
- High severity. CVSS v3 base score is 7.5 out of 10.
- Is CVE-2025-2099 known to be exploited?
- 3 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.