HighVulnerability

CVE-2026-6859: InstructLab code execution via untrusted HuggingFace model loading

Source: NVD(opens in a new tab)
Identifier: CVE-2026-6859
Published: April 22, 2026
Record updated: October 9, 2026

Affected: instructlab <= 0.26.1
Fixed in: No fixed version was stated when the source was last read.
Known exploitation: Not listed in the CISA Known Exploited Vulnerabilities catalog at the last check.
EPSS: 0.4%

Summary

CVE-2026-6859 affects InstructLab. The `linux_train.py` script hardcodes `trust_remote_code=True` when loading models from HuggingFace, so a remote attacker can achieve arbitrary Python code execution by persuading a user to run `ilab train/download/generate` with a crafted malicious model from the HuggingFace Hub. The weakness is classified as CWE-829, and NVD had not yet provided an assessment at publication.

Mitigation

The source does not state a fix yet. Check the original advisory for updates.

Details

Scores and exploitation

CVSS score: 8.8(high)
CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Attack vector: network
Attack complexity: low
Privileges required: none
User interaction: required
EPSS: 0.4%Estimated probability that this CVE is exploited in the next 30 days, from the FIRST Exploit Prediction Scoring System. Read on November 8, 2026.
Disclosure date: April 22, 2026

Weaknesses and techniques

Weakness (CWE): CWE-829
Attack pattern (CAPEC): CAPEC-437
AI threat technique (MITRE ATLAS): AML.T0010

Affected

Packages: instructlab@<= 0.26.1
Vendors: HuggingFace

Classification

Attack type: Supply chain
Attack sophistication: Moderate
AI component targeted: Training data
Impact: Confidentiality,
Integrity,
Availability
Labels: security

How this record was produced

Summaries, mitigations and labels on this page are generated automatically from the source. The linked source is authoritative. The source gives this advisory a description and no title, so the title above is a headline generated from the source text.

Original source: https://nvd.nist.gov/vuln/detail/CVE-2026-6859

First tracked: April 22, 2026 at 02:08 PM ET, from NVD/CVE Database

Classifier: claude-haiku-5-5, prompt v4

Classifier confidence: 90% (self-assessed)

Topics

Model and package supply chain

Summary

Mitigation

Topics

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