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CVE-2025-6921 Detail

Description

The huggingface/transformers library, versions prior to 4.53.0, is vulnerable to Regular Expression Denial of Service (ReDoS) in the AdamWeightDecay optimizer. The vulnerability arises from the _do_use_weight_decay method, which processes user-controlled regular expressions in the include_in_weight_decay and exclude_from_weight_decay lists. Malicious regular expressions can cause catastrophic backtracking during the re.search call, leading to 100% CPU utilization and a denial of service. This issue can be exploited by attackers who can control the patterns in these lists, potentially causing the machine learning task to hang and rendering services unresponsive.


Metrics

NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.
CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

References to Advisories, Solutions, and Tools

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URL Source(s) Tag(s)
https://github.com/huggingface/transformers/commit/47c34fba5c303576560cb29767efb452ff12b8be huntr.dev
https://huntr.com/bounties/287d15a7-6e7c-45d2-8c05-11e305776f1f huntr.dev

Weakness Enumeration

CWE-ID CWE Name Source
CWE-400 Uncontrolled Resource Consumption huntr.dev  

Change History

1 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2025-6921
NVD Published Date:
09/23/2025
NVD Last Modified:
09/24/2025
Source:
huntr.dev