Segfault in Tensorflow

Impact

In eager mode, TensorFlow does not set the session state. Hence, calling tf.raw_ops.GetSessionHandle or tf.raw_ops.GetSessionHandleV2 results in a null pointer dereference:
https://github.com/tensorflow/tensorflow/blob/0e68f4d3295eb0281a517c3662f6698992b7b2cf/tensorflow/core/kernels/session_ops.cc#L45

In the above snippet, in eager mode, ctx->session_state() returns nullptr. Since code immediately dereferences this, we get a segmentation fault.

Patches

We have patched the issue in 9a133d73ae4b4664d22bd1aa6d654fec13c52ee1 and will release patch releases for all versions between 1.15 and 2.3.

We recommend users to upgrade to TensorFlow 1.15.4, 2.0.3, 2.1.2, 2.2.1, or 2.3.1.

For more information

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

Attribution

This vulnerability has been reported by members of the Aivul Team from Qihoo 360.