CVE-2026-6859 — instructlab
HIGHCVE-2026-6859 is a high-severity (CVSS 8.8) CWE-829 vulnerability in instructlab. The records list no fixed version yet; check the vendor advisory below and apply the mitigations in the meantime.
InstructLab Includes Functionality from Untrusted Control Sphere
Exploitation Status
No confirmed exploitation observed yet
- A successful exploit gives an attacker total control of the affected component, not partial access.
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2026-6859.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
Where this sits among everything scored
Real-World Exposure
instructlabReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects PyPI packages — download data is not available via public APIs for these ecosystems.
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 Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐍PyPI | instructlab | all versions | No fix |
Affected Products
enterprise linux airedhatinstructlabredhatDetection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for instructlab, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Remediation status
The records we use list no patched version of instructlab for CVE-2026-6859. Check the maintainer's advisory, and where your build allows, override or pin the dependency away from the vulnerable range.
Mitigate without a patch
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
Fixing This On Your OS
If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project.
To mitigate this issue, only use models from trusted sources when performing `instructlab` operations. Review the origin and integrity of any HuggingFace model before using it with `ilab train/download/generate`. Consider running `instructlab` commands within a sandboxed or isolated environment to limit the potential impact of executing untrusted code.Source: Red Hat security advisory for CVE-2026-6859 (CC BY 4.0)
Frequently Asked Questions
Is CVE-2026-6859 in your dependencies?
Find it across PyPI, including transitive dependencies.