Out of bounds write in Tensorflow
### Impact
TensorFlow is vulnerable to a heap OOB write in Grappler
https://github.com/tensorflow/tensorflow/blob/a1320ec1eac186da1d03f033109191f715b2b130/tensorflow/core/grappler/costs/graph_properties.cc#L1132-L1141:
```cc
Status SetUnknownShape(const NodeDef* node, int output_port) {
shape_inference::ShapeHandle shape =
GetUnknownOutputShape(node, output_port);
InferenceContext* ctx = GetContext(node);
if (ctx == nullptr) {
return errors::InvalidArgument("Missing context");
}
ctx->set_output(output_port, shape);
return Status::OK();
}
```
The `set_output`
https://github.com/tensorflow/tensorflow/blob/a1320ec1eac186da1d03f033109191f715b2b130/tensorflow/core/framework/shape_inference.h#L394 function writes to an array at the specified index:
```cc
void set_output(int idx, ShapeHandle shape) { outputs_.at(idx) = shape; }
```
Hence, this gives a malicious user a write primitive.
### Patches
We have patched the issue in GitHub commit 97282c6d0d34476b6ba033f961590b783fa184cd
https://github.com/tensorflow/tensorflow/commit/97282c6d0d34476b6ba033f961590b783fa184cd.
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.
### For more information
Please consult our security guide
https://github.com/tensorflow/tensorflow/blob/master/SECURITY.md for more information regarding the security model and how to contact us with issues and questions.