Huggingface Transformers
CVE-2026-5241
A vulnerability in the LightGlue model loading path of huggingface/transformers version 5.2.0 allows an attacker-controlled model repository to execute arbitrary code during model initialization. The issue arises because the `trust_remote_code` parameter, intended to prevent remote code execution, is overridden by untrusted serialized configuration data in a nested code path. Specifically, when loading a LightGlue model using `AutoModel.from_pretrained()` with `trust_remote_code=False`, the `LightGlueConfig` reads the `trust_remote_code` value from the untrusted `config.json` file and propagates it into nested `AutoConfig.from_pretrained()` calls. This results in the execution of attacker-provided Python modules, even when the victim explicitly disables remote code execution. The vulnerability poses a high risk for environments such as API inference servers, research notebooks, CI/CD pipelines, and model evaluation workers, potentially leading to credential theft, lateral movement, or persistence/backdoor deployment.
What this means for your business
- It affects Huggingface Transformers. It matters if your company, or a supplier that handles your data, runs it.
- Code showing how to exploit it has been published, but real attacks have not been confirmed.
- An attacker can use it remotely, over a network, without a login, but only after tricking someone into an action such as opening a file or a link.
- FIRST's prediction model gives it a 0.6% chance of attack attempts being seen in the next 30 days, ranking above 47% of all known flaws.
What to do
- 1Check whether your company or your suppliers run Huggingface Transformers, and which version. The affected versions are listed further down this page.
- 2If you do, apply the vendor's fix. A patch or vendor advisory has been published.
Not sure if your company is exposed?
Fastnexa’s certified penetration testers can check whether attackers could use this flaw, or others like it, against your websites, apps and network. The full test is free for our first 10 founding clients until 31 December 2026.
Scoring
- CVSS
- 9.6 (v3.1)
- Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H- Weakness
- CWE-829
- Assigned by
- security@huntr.dev
Dates
- Published
- 2026-06-03
- Last modified
- 2026-08-28
- Sources
- NVD
Affected products
- Huggingface Transformers5.2.0
As listed in the NVD configuration data. Not a statement about your estate.
References
- https://github.com/huggingface/transformers/commit/676559d5022b74aaa0cee1cee0842b7f27c5320e
- https://huntr.com/bounties/ceb3ce1a-4c45-497a-b25e-cb9a7685e619
- https://access.redhat.com/errata/RHSA-2026:34456
- https://access.redhat.com/errata/RHSA-2026:37275
- https://access.redhat.com/errata/RHSA-2026:42644
- https://access.redhat.com/errata/RHSA-2026:60520
- https://access.redhat.com/security/cve/CVE-2026-5241
- https://bugzilla.redhat.com/show_bug.cgi?id=2484384
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-5241.json