CVE-2021-29538: Google Tensorflow

Medium severity, CVSS 5.5. EPSS: 0.2% chance of exploitation in the next 30 days.

TensorFlow is an end-to-end open source platform for machine learning. An attacker can cause a division by zero to occur in `Conv2DBackpropFilter`. This is because the implementation(https://github.com/tensorflow/tensorflow/blob/1b0296c3b8dd9bd948f924aa8cd62f87dbb7c3da/tensorflow/core/kernels/conv_grad_filter_ops.cc#L513-L522) computes a divisor based on user provided data (i.e., the shape of the tensors given as arguments). If all shapes are empty then `work_unit_size` is 0. Since there is no check for this case before division, this results in a runtime exception, with potential to be abused for a denial of service. The fix will be included in TensorFlow 2.5.0. We will also cherrypick this commit on TensorFlow 2.4.2, TensorFlow 2.3.3, TensorFlow 2.2.3 and TensorFlow 2.1.4, as these are also affected and still in supported range.

Affected products

• Google Tensorflow: before 2.1.4 (fixed in 2.1.4); from 2.2.0, before 2.2.3 (fixed in 2.2.3); from 2.3.0, before 2.3.3 (fixed in 2.3.3); from 2.4.0, before 2.4.2 (fixed in 2.4.2)

Published 2021-05-14. Last modified 2026-06-17.