CVE-2026-44513 Diffusers: `trust_remote_code` bypass via `custom_pipeline` and local custom components
- Exploited in the wild
- Not known
- Fix
- Available
What is CVE-2026-44513?
CVE-2026-44513 is a high-severity vulnerability in huggingface diffusers, published on 14 May 2026.
Official description
Diffusers is the a library for pretrained diffusion models. Prior to 0.38.0, 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. 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. 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. 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. This vulnerability is fixed in 0.38.0.
Which versions are affected by CVE-2026-44513?
3 open source packages ship an affected version, including diffusers. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
diffusers PyPI | All versions | 0.38.0 |
diffusers PyPI | All versions | 0.38.0 |
diffusers PyPI | All versions | 0.38.0 |
Products include Huggingface Diffusers.
How do I fix CVE-2026-44513?
Upgrade diffusers to 0.38.0 or later.
Is CVE-2026-44513 being exploited?
There is no known exploitation of CVE-2026-44513 in the wild and no public exploit code.
Other vulnerabilities in huggingface diffusers
Sources
Also known as GHSA-98h9-4798-4q5v, PYSEC-2026-40.