CVE-2026-47749 stable-diffusion.cpp: Heap buffer overflow in SHORT_BINUNICODE parsing for PyTorch checkpoint files
Heap buffer overflow in stable-diffusion.cpp allows attackers to execute code or crash the application via crafted PyTorch checkpoint files.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- A user has to click or open something
- Fix
- None listed
What is CVE-2026-47749?
CVE-2026-47749 is a high-severity memory corruption vulnerability in leejet stable-diffusion.cpp, published on 16 Jun 2026. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.
Official description
stable-diffusion.cpp is a pure C/C++ library for running diffusion model (Stable Diffusion, Flux, Wan, Qwen Image, Z-Image, and more) inference. Versions prior to master-584-0a7ae07 are vulnerable to heap buffer overflow in SHORT_BINUNICODE parsing for PyTorch checkpoint files. The pickle .ckpt parser in src/model.cpp contained a heap buffer overflow vulnerability in the SHORT_BINUNICODE opcode handler. The issue was caused by sign confusion on the opcode length field. A crafted .ckpt file could trigger memcpy with a very large length derived from a negative signed value, causing immediate heap corruption. Any application using affected stable-diffusion.cpp releases to load untrusted .ckpt model files could be vulnerable. A malicious checkpoint file could cause heap corruption through memcpy with an attacker-controlled length. This may lead to process crash and could potentially be leveraged for code execution depending on heap layout. The attack requires the victim or application to load a .ckpt file from an untrusted source, such as a downloaded model from a model sharing site. The issue has been resolved in version master-584-0a7ae07. If developers are unable to immediately update their applications they can work around this issue by not loading .ckpt checkpoint files from untrusted sources, and referring to trusted model sources and safer formats such as .safetensors where possible.
Which versions are affected by CVE-2026-47749?
It affects 1 product.
Products include Leejet Stable-Diffusion.cpp.
How do I fix CVE-2026-47749?
No fix has been published for CVE-2026-47749 yet. Limit exposure of the affected software until one is available.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2026-47749 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-47749 exists.
Other vulnerabilities in leejet stable-diffusion.cpp
Sources
Also known as GHSA-2c29-5hxg-fv9g.