CVE-2026-53923

Name of the Vulnerable Software and Affected Versions vLLM versions 0.5.5 through 0.23.1rc0

Description Integer truncation of tensor dimensions in GGUF dequantize kernels within csrc/quantization/gguf/gguf kernel.cu leads to partial tensor processing. The output tensor is allocated at full size using torch::empty, which creates uninitialized memory, but the dequantize CUDA kernel processes only a truncated number of elements because the element count parameter k in the to cuda ggml t function pointer is defined as a 32-bit int. When the product of dimensions m * n exceeds INT MAX, the truncated value is used as the kernel launch grid size, leaving the remaining portion of the tensor unfilled.

In multi-tenant inference deployments, this residual GPU memory may contain tensor data from other users' inference requests, resulting in information disclosure. This issue affects the following functions in csrc/quantization/gguf/gguf kernel.cu:

Recommendations Update vLLM to version 0.23.1rc0 or later.