Vulnerability · Published Nov 5, 2026 · Assigned by GitHub_M
CVE-2026-70659stable-diffusion.cpp: Heap out-of-bounds write in the imatrix loader (`load_imatrix`) via a duplicate tensor name
High 7.8
In plain English
A high-severity out-of-bounds write in stable-diffusion.cpp from leejet. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.1% (higher than 2% of all known vulnerabilities).
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. From master-742-1a13107 until master-763-4fcc6fe, IMatrixCollector::load_imatrix in src/runtime/imatrix.cpp reuses the values and counts vectors for entries with the same tensor name but resizes them only when they are empty. An untrusted .imatrix file can provide a small nval for the first entry and a larger nval for a second entry with the same name, causing the accumulation loop to write attacker-controlled floating-point and integer values beyond both heap buffers. Loading the file through the --imat-in conversion path can corrupt the heap or crash the process before a model is required. This issue is fixed in master-763-4fcc6fe.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| leejet | stable-diffusion.cpp | < master-763-4fcc6fe |
Weakness: CWE-787, CWE-1284 · Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
References
- https://github.com/leejet/stable-diffusion.cpp/security/advisories/GHSA-6q7q-2v9c-x8m7 x_refsource_CONFIRM
- https://github.com/leejet/stable-diffusion.cpp/pull/1750 x_refsource_MISC
- https://github.com/leejet/stable-diffusion.cpp/commit/4fcc6fef10c6f686801c6e257b22cd6a3deb906b x_refsource_MISC
- https://github.com/leejet/stable-diffusion.cpp/releases/tag/master-763-4fcc6fe x_refsource_MISC