GHSA-98h9-4798-4q5v

Suggest an improvement
Source
https://github.com/advisories/GHSA-98h9-4798-4q5v
Import Source
https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/05/GHSA-98h9-4798-4q5v/GHSA-98h9-4798-4q5v.json
JSON Data
https://api.osv.dev/v1/vulns/GHSA-98h9-4798-4q5v
Aliases
  • CVE-2026-44513
Related
Published
2026-05-07T05:31:17Z
Modified
2026-05-12T04:44:31.276681035Z
Severity
  • 8.8 (High) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H CVSS Calculator
Summary
Diffusers has a `trust_remote_code` bypass via `custom_pipeline` and local custom components
Details

Impact

A trust_remote_code bypass in DiffusionPipeline.from_pretrained allows arbitrary remote code execution despite the user passing trust_remote_code=False (or omitting it, which is the default). The vulnerability has three variants, all sharing the same root cause — the trust_remote_code gate was implemented inside DiffusionPipeline.download() rather than at the actual dynamic-module load site, so any code path that bypassed or short-circuited download() also bypassed the security check:

  1. Cross-repo custom_pipeline. DiffusionPipeline.from_pretrained('repoA', custom_pipeline='attacker/repoB', trust_remote_code=False) — the gate evaluated against repoA's file list rather than repoB's, so repoB's pipeline.py was loaded and executed.
  2. Local snapshot + Hub custom_pipeline. DiffusionPipeline.from_pretrained('/local/snapshot', custom_pipeline='attacker/repoB', trust_remote_code=False) — the local-path branch never invoked download(), so the gate was never reached and remote code from repoB executed.
  3. Local snapshot with custom components. DiffusionPipeline.from_pretrained('/local/snapshot', trust_remote_code=False) where the snapshot contains custom component files (e.g. unet/my_unet_model.py) referenced from model_index.json — same root cause; the local path skipped download() and custom component code executed.

Silent remote code execution on the victim's machine. Anyone calling DiffusionPipeline.from_pretrained with custom pipelines is impacted.

Patches

Yes. Fixed in diffusers 0.38.0 via PR #13448. All users on versions < 0.38.0 should upgrade:

pip install --upgrade "diffusers>=0.38.0"

The fix moves the trust_remote_code gate out of DiffusionPipeline.download() and into get_cached_module_file in src/diffusers/utils/dynamic_modules_utils.py, which is the actual chokepoint for every dynamic module load (local, Hub, or community mirror). All three variants now raise ValueError instead of executing untrusted code.

Workarounds

If upgrading immediately is not possible:

  • Only call from_pretrained with pretrained_model_name_or_path, custom_pipeline, and local snapshot directories from fully trusted sources that have been audited.
  • Do not pass custom_pipeline= pointing at a Hub repository different from the primary pretrained_model_name_or_path before reading its pipeline.py.
  • Before calling from_pretrained on a local snapshot, inspect the snapshot for unexpected *.py files, especially under component subdirectories (unet/, scheduler/, etc.) and at the snapshot root.

These are mitigations, not fixes — the only complete remediation is upgrading to 0.38.0.

Resources

  • Fix: https://github.com/huggingface/diffusers/pull/13448
  • Original issue: https://github.com/huggingface/diffusers/issues/13446
  • Release notes: https://github.com/huggingface/diffusers/releases/tag/v0.38.0
  • CWE-94: https://cwe.mitre.org/data/definitions/94.html
Database specific 
{
    "github_reviewed": true,
    "github_reviewed_at": "2026-05-07T05:31:17Z",
    "nvd_published_at": null,
    "severity": "HIGH",
    "cwe_ids": [
        "CWE-94"
    ]
}
References

Affected packages

PyPI / diffusers

Package

Name
diffusers
View open source insights on deps.dev
Purl
pkg:pypi/diffusers

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected
Fixed
0.38.0

Affected versions

0.*
0.0.1
0.0.2
0.0.3
0.0.4
0.1.0
0.1.1
0.1.2
0.1.3
0.2.0
0.2.1
0.2.2
0.2.3
0.2.4
0.3.0
0.4.0
0.4.1
0.4.2
0.5.0
0.5.1
0.6.0
0.7.0
0.7.1
0.7.2
0.8.0
0.8.1
0.9.0
0.10.0
0.10.1
0.10.2
0.11.0
0.11.1
0.12.0
0.12.1
0.13.0
0.13.1
0.14.0
0.15.0
0.15.1
0.16.0
0.16.1
0.17.0
0.17.1
0.18.0
0.18.1
0.18.2
0.19.0
0.19.1
0.19.2
0.19.3
0.20.0
0.20.1
0.20.2
0.21.0
0.21.1
0.21.2
0.21.3
0.21.4
0.22.0
0.22.1
0.22.2
0.22.3
0.23.0
0.23.1
0.24.0
0.25.0
0.25.1
0.26.0
0.26.1
0.26.2
0.26.3
0.27.0
0.27.1
0.27.2
0.28.0
0.28.1
0.28.2
0.29.0
0.29.1
0.29.2
0.30.0
0.30.1
0.30.2
0.30.3
0.31.0
0.32.0
0.32.1
0.32.2
0.33.0
0.33.1
0.34.0
0.35.0
0.35.1
0.35.2
0.36.0
0.37.0
0.37.1

Database specific

source 
"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/05/GHSA-98h9-4798-4q5v/GHSA-98h9-4798-4q5v.json"