Skip to main content
← All vulnerabilities
CVE-2021-29550PYSEC-2021-478BIT-TENSORFLOW-2021-29550GHSA-F78G-Q7R4-9WCVPYSEC-2021-187PYSEC-2021-676

Division by 0 in `FractionalAvgPool`

Published
Last modified
published
Not listed in CISA KEV
Fix
Fixed in 2.1.4, 2.2.3, 2.3.3, 2.4.2, 2.2.0rc0, and 3 more
None on Exploit-DB, Metasploit or GitHub

Summary

TensorFlow is an end-to-end open source platform for machine learning. An attacker can cause a runtime division by zero error and denial of service in `tf.raw_ops.FractionalAvgPool`. This is because the implementation(https://github.com/tensorflow/tensorflow/blob/acc8ee69f5f46f92a3f1f11230f49c6ac266f10c/tensorflow/core/kernels/fractional_avg_pool_op.cc#L85-L89) computes a divisor quantity by dividing two user controlled values. The user controls the values of `input_size[i]` and `pooling_ratio_[i]` (via the `value.shape()` and `pooling_ratio` arguments). If the value in `input_size[i]` is smaller than the `pooling_ratio_[i]`, then the floor operation results in `output_size[i]` being 0. The `DCHECK_GT` line is a no-op outside of debug mode, so in released versions of TF this does not trigger. Later, these computed values are used as arguments(https://github.com/tensorflow/tensorflow/blob/acc8ee69f5f46f92a3f1f11230f49c6ac266f10c/tensorflow/core/kernels/fractional_avg_pool_op.cc#L96-L99) to `GeneratePoolingSequence`(https://github.com/tensorflow/tensorflow/blob/acc8ee69f5f46f92a3f1f11230f49c6ac266f10c/tensorflow/core/kernels/fractional_pool_common.cc#L100-L108). There, the first computation is a division in a modulo operation. Since `output_length` can be 0, this results in runtime crashing. 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.

Timeline

  1. CVE published
  2. Record last updated

Affected versions

  • tensorflow tensorflow

    fixed in 2.1.4; From 2.2.0 · fixed in 2.2.3; From 2.3.0 · fixed in 2.3.3; From 2.4.0 · fixed in 2.4.2

  • tensorflow-cpuPyPI

    fixed in 2.2.0rc0; From 2.2.0 · fixed in 2.3.0rc0; From 2.3.0 · fixed in 2.3.4; From 2.4.0 · fixed in 2.4.3

  • tensorflowPyPI

    fixed in 2.1.4

  • tensorflowPyPI

    From 2.2.0 · fixed in 2.2.3

  • tensorflowPyPI

    From 2.3.0 · fixed in 2.3.3

  • tensorflowPyPI

    From 2.4.0 · fixed in 2.4.2

  • tensorflow-cpuPyPI

    fixed in 2.1.4

  • tensorflow-cpuPyPI

    From 2.2.0 · fixed in 2.2.3

  • tensorflow-cpuPyPI

    From 2.3.0 · fixed in 2.3.3

  • tensorflow-cpuPyPI

    From 2.4.0 · fixed in 2.4.2

  • tensorflow-gpuPyPI

    fixed in 2.1.4

  • tensorflow-gpuPyPI

    From 2.2.0 · fixed in 2.2.3

  • tensorflow-gpuPyPI

    From 2.3.0 · fixed in 2.3.3

  • tensorflow-gpuPyPI

    From 2.4.0 · fixed in 2.4.2

  • tensorflow-gpuPyPI

    fixed in 2.2.0rc0; From 2.2.0 · fixed in 2.3.0rc0; From 2.3.0 · fixed in 2.3.4; From 2.4.0 · fixed in 2.4.3

  • tensorflowPyPI

    fixed in 2.2.0rc0; From 2.2.0 · fixed in 2.3.0rc0; From 2.3.0 · fixed in 2.3.4; From 2.4.0 · fixed in 2.4.3

References 2

GitHub · tensorflow/tensorflow