TransformersGHSA-rcv9-qm8p-9p6j
Hugging Face Transformers library has Regular Expression Denial of Service
Medium5.3CVE-2025-6051 · Published Sep 14, 2025 · updated Sep 10, 2026
Affected versions
| Package | Affected | Fixed in |
|---|---|---|
| transformers PyPI | < 4.53.0 | 4.53.0 |
Details and references
A Regular Expression Denial of Service (ReDoS) vulnerability was discovered in the Hugging Face Transformers library, specifically within the `normalize_numbers()` method of the `EnglishNormalizer` class. This vulnerability affects versions up to 4.52.4 and is fixed in version 4.53.0. The issue arises from the method's handling of numeric strings, which can be exploited using crafted input strings containing long sequences of digits, leading to excessive CPU consumption. This vulnerability impacts text-to-speech and number normalization tasks, potentially causing service disruption, resource exhaustion, and API vulnerabilities.
- CVSS 3.0
- CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
- Severity from
- GitHub (reviewed advisory)
- Weakness
- CWE-1333
- Also known as
- CVE-2025-6051, PYSEC-2026-1988
- nvd.nist.gov/vuln/detail/CVE-2025-6051
- github.com/huggingface/transformers/pull/38844
- github.com/huggingface/transformers/commit/54a02160eb030da9be18231c77791f2eb3a52216
- github.com/huggingface/transformers/commit/ba8eaba9865618253f997784aa565b96206426f0
- github.com/huggingface/transformers
- huntr.com/bounties/af929523-7b59-418a-bf55-301830b2ac9d
More Transformers advisories
All Transformers| Date | Advisory | Severity | Fixed in |
|---|---|---|---|
| Sep 122025 | Hugging Face Transformers is vulnerable to ReDoS through its MarianTokenizer CVE-2025-6638Medium5.3fixed in 4.53.0 | Medium5.3 | 4.53.0 |
| Sep 232025 | Hugging Face Transformers vulnerable to Regular Expression Denial of Service (ReDoS) in the AdamWeightDecay optimizer CVE-2025-6921Medium5.3fixed in 4.53.0 | Medium5.3 | 4.53.0 |
| Aug 62025 | Hugging Face Transformers Regular Expression Denial of Service (ReDoS) vulnerability CVE-2025-5197Medium5.3fixed in 4.53.0 | Medium5.3 | 4.53.0 |
| Jul 112025 | Transformers is vulnerable to ReDoS attack through its DonutProcessor class CVE-2025-3933Medium5.3fixed in 4.52.1 | Medium5.3 | 4.52.1 |
| Jul 72025 | Transformers vulnerable to ReDoS attack through its SETTING_RE variable CVE-2025-3262Medium5.3fixed in 4.51.0 | Medium5.3 | 4.51.0 |
| Jul 72025 | Transformers vulnerable to ReDoS attack through its get_imports() function CVE-2025-3264Medium5.3fixed in 4.51.0 | Medium5.3 | 4.51.0 |