CVE-2026-44513
Description
A flaw was found in Diffusers, a library for pretrained diffusion models. A remote attacker could exploit a bypass in the trust_remote_code mechanism within the DiffusionPipeline.from_pretrained function. This vulnerability allows for arbitrary remote code execution, even when the user explicitly sets trust_remote_code=False or omits it. The issue stems from the security check being incorrectly placed, allowing malicious code to be loaded and executed by bypassing the intended security gate.
Statement
This is an Important vulnerability in Diffusers, a library used in Red Hat AI/ML offerings, that allows arbitrary remote code execution. The trust_remote_code security mechanism in DiffusionPipeline.from_pretrained can be bypassed, enabling the loading and execution of malicious code despite explicit security settings. This misplacement of the security check increases the risk in environments where users load models from external or untrusted repositories.
Mitigation
Use DiffusionPipeline.from_pretrained() only with model paths, custom pipelines,
and local snapshots from fully trusted and audited sources. Avoid setting
custom_pipeline= to a Hub repository that differs from the primary model path
unless its pipeline.py has been manually reviewed. When loading a local snapshot, check for unexpected *.py files at the snapshot root and under component subdirectories (unet/, scheduler/, etc.) before calling from_pretrained.
The only complete fix is upgrading to diffusers 0.38.0.
Common Vulnerability Scoring System (CVSS) Score Details
Info alert:Important note
CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).
The following CVSS metrics and score provided are preliminary and subject to review.
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 8.8 | N/A | 8.8 |
| Attack Vector | Network | N/A | Network |
| Attack Complexity | Low | N/A | Low |
| Privileges Required | None | N/A | None |
| User Interaction | Required | N/A | Required |
| Scope | Unchanged | N/A | Unchanged |
| Confidentiality | High | N/A | High |
| Integrity Impact | High | N/A | High |
| Availability Impact | High | N/A | High |
Vector
Red Hat: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
cve.org: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Understanding the Weakness (CWE)
Access Control
Technical Impact: Bypass Protection Mechanism
Frequently Asked Questions
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