CVE-2025-6921: medium-severity vulnerability in huggingface/transformers
Regular Expression Denial of Service (ReDoS) in huggingface/transformers
Published
E-mail alert when it lands in KEV, gets a public PoC or its score goes up.
13Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 5.3epss 0.5%
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.
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
Affected products
huggingface · huggingface/transformersRelated CVEs — huggingface/transformers
In the same product, most dangerous first.
CVE-2024-3568LOWArbitrary Code Execution via Deserialization in huggingface/transformersEPSS 2.1%CVE-2023-6730CRITICALDeserialization of Untrusted Data in huggingface/transformersEPSS 0.9%CVE-2024-12720MEDIUMRegular Expression Denial of Service (ReDoS) in huggingface/transformersEPSS 0.7%CVE-2023-7018CRITICALDeserialization of Untrusted Data in huggingface/transformersEPSS 0.7%CVE-2026-4372HIGHArbitrary Remote Code Execution via `_attn_implementation_internal` Config Injection in huggingface/transformersEPSS 0.7%CVE-2025-2099MEDIUMRegular Expression Denial of Service (ReDoS) in huggingface/transformersEPSS 0.6%