tract-nnef: integer overflow in NNEF `.dat` tensor parser yields an out-of-bounds read on model load

Summary

Tract is a tiny, no-nonsense, self-contained TensorFlow and ONNX inference toolkit. Prior to 0.21.16, 0.22.2, and 0.23.1, tract-nnef uses unchecked usize multiplication in nnef/src/tensors.rs read_tensor for attacker-controlled tensor dimensions, the allocation size, and the reported tensor length. Loading a crafted NNEF archive through model_for_path or model_for_read reaches the default DatLoader and can make the wrapped size check accept a small allocation while data/src/tensor.rs as_slice_unchecked creates a much larger logical slice. Model construction through as_uniform can then read beyond the heap allocation and disclose adjacent data, and later access can terminate the process with a segmentation fault. The affected dense numeric tensor path does not include the independently guarded bool, String, or block-quant paths, and no out-of-bounds write or code execution was demonstrated. This issue is fixed in versions 0.21.16, 0.22.2, and 0.23.1.

Timeline

1. Sep 14, 2026, 7:47 PM UTCCVE published
2. Sep 14, 2026, 8:09 PM UTCCISA SSVC assessment

   Exploitation: poc · Automatable: no · Technical impact: partial

3. Sep 14, 2026, 8:09 PM UTCRecord last updated

Affected versions

• sonos tract

  fixed in 0.21.16; From 0.22.0 · fixed in 0.22.2; From 0.23.0 · fixed in 0.23.1

• tract-nnefcrates.io

  From 0.23.0 · fixed in 0.23.1

• tract-nnefcrates.io

  From 0.22.0 · fixed in 0.22.2

• tract-nnefcrates.io

  fixed in 0.21.16

• tract-nnefcrates.io

  From 0.0.0-0 · fixed in 0.21.16; From 0.22.0 · fixed in 0.22.2; From 0.23.0 · fixed in 0.23.1

References 7