CVE-2026-6859: Instructlab: instructlab: arbitrary code execution due to hardcoded `trust_remote_code=true`

Severity: high (CVSS 8.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.4% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-04-22 · updated 2026-10-26
Weakness: CWE-829

Description

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.

Affected products

RedHat Enterprise Linux Ai: 3.0
RedHat Instructlab: all versions

References

https://access.redhat.com/security/cve/CVE-2026-6859
https://bugzilla.redhat.com/show_bug.cgi?id=2459998
https://access.redhat.com/security/cve/CVE-2026-6859
https://bugzilla.redhat.com/show_bug.cgi?id=2459998
https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-6859.json

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