CVE-2025-5197: transformers — Exploit & Fix

Description

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.

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CVSS v3.1 Score

5.3

MEDIUM

CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

Weakness Type (CWE)

CWE-1333 CWE-1333

Affected Products

Vendor	Product	Versions
huggingface	transformers	< 4.53.0

References

Advisories & Patches

https://github.com/huggingface/transformers/commit/944b56000be5e9b61af8301aa340838770ad8a0b https://huntr.com/bounties/3f8b3fd0-166b-46e7-b60f-60dd9d2678bf https://huntr.com/bounties/3f8b3fd0-166b-46e7-b60f-60dd9d2678bf

Exploits

https://huntr.com/bounties/3f8b3fd0-166b-46e7-b60f-60dd9d2678bf https://huntr.com/bounties/3f8b3fd0-166b-46e7-b60f-60dd9d2678bf

Frequently Asked Questions

What is CVE-2025-5197? +

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. It has a CVSS v3.1 base score of 5.3 (MEDIUM).

How severe is CVE-2025-5197? +

CVE-2025-5197 has a CVSS v3.1 score of 5.3 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.

What products are affected by CVE-2025-5197? +

CVE-2025-5197 affects products from huggingface, specifically: transformers. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2025-5197? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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