Bug 2459998 (CVE-2026-6859)

Summary: CVE-2026-6859 instructlab: InstructLab: Arbitrary code execution due to hardcoded `trust_remote_code=True`
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security <prodsec-ir-bot>
Status: NEW --- QA Contact:
Severity: high Docs Contact:
Priority: high    
Version: unspecifiedCC: bbrownin
Target Milestone: ---Keywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in InstructLab. The `linux_train.py` script hardcodes `trust_remote_code=True` when loading models from HuggingFace. This allows a remote attacker to achieve arbitrary Python code execution by convincing a user to run `ilab train/download/generate` with a specially crafted malicious model from the HuggingFace Hub. This vulnerability can lead to complete system compromise.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Description OSIDB Bzimport 2026-04-21 07:51:02 UTC
InstructLab hardcodes trust_remote_code=True in linux_train.py for all HuggingFace from_pretrained() calls. This enables arbitrary Python code execution from malicious model repositories on HuggingFace Hub. Attacker needs only a free HuggingFace account; victim runs ilab train/download/generate with the malicious model name.

Upstream notification: security-reporting bounced for external senders. Filed via Red Hat.