The [implementation of OpLevelCostEstimator::CalculateOutputSize](https://github.com/tensorflow/tensorflow/blob/a1320ec1eac186da1d03f033109191f715b2b130/tensorflow/core/grappler/costs/op level cost estimator.cc#L1598-L1617) is vulnerable to an integer overflow if an attacker can create an operation which would involve tensors with large enough number of elements:

for (const auto& dim : output shape.dim()) {
 output size *= dim.size();
} 

Here, we can have a large enough number of dimensions in output shape.dim() or just a small number of dimensions being large enough to cause an overflow in the multiplication.

We have patched the issue in GitHub commit b9bd6cfd1c50e6807846af9a86f9b83cafc9c8ae.

The fix will be included in TensorFlow 2.8.0. We will also cherrypick this commit on TensorFlow 2.7.1, TensorFlow 2.6.3, and TensorFlow 2.5.3, as these are also affected and still in supported range.

Please consult our security guide for more information regarding the security model and how to contact us with issues and questions.