Hugging Face Transformers Regular Expression Denial of Service (ReDoS) vulnerability
Medium5.3CVE-2025-5197 · Published Aug 6, 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 exists in the Hugging Face Transformers library, specifically in the `convert_tf_weight_name_to_pt_weight_name()` function. This function, responsible for converting TensorFlow weight names to PyTorch format, uses a regex pattern `/[^/]*___([^/]*)/` that can be exploited to cause excessive CPU consumption through crafted input strings due to catastrophic backtracking. The vulnerability affects versions up to 4.51.3 and is fixed in version 4.53.0. This issue can lead to service disruption, resource exhaustion, and potential API service vulnerabilities, impacting model conversion processes between TensorFlow and PyTorch formats.
- 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-2025-5197, PYSEC-2026-1983
More Transformers advisories
All Transformers| Date | Advisory | Severity | Fixed in |
|---|---|---|---|
| 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 |
| Jul 72025 | Transformers's Improper Input Validation vulnerability can be exploited through username injection CVE-2025-3777Low3.5fixed in 4.52.1 | Low3.5 | 4.52.1 |
| Jul 72025 | Transformers's ReDoS vulnerability in get_configuration_file can lead to catastrophic backtracking CVE-2025-3263Medium5.3fixed in 4.51.0 | Medium5.3 | 4.51.0 |
| 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 |