Vulnerability Description
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.
CVSS Score
LOW
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Tensorflow | < 2.1.4 |
Related Weaknesses (CWE)
References
- https://github.com/tensorflow/tensorflow/commit/548b5eaf23685d86f722233d8fbc21d0PatchThird Party Advisory
- https://github.com/tensorflow/tensorflow/security/advisories/GHSA-f78g-q7r4-9wcvExploitPatchThird Party Advisory
- https://github.com/tensorflow/tensorflow/commit/548b5eaf23685d86f722233d8fbc21d0PatchThird Party Advisory
- https://github.com/tensorflow/tensorflow/security/advisories/GHSA-f78g-q7r4-9wcvExploitPatchThird Party Advisory
FAQ
What is CVE-2021-29550?
CVE-2021-29550 is a vulnerability with a CVSS score of 2.5 (LOW). 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 t...
How severe is CVE-2021-29550?
CVE-2021-29550 has been rated LOW with a CVSS base score of 2.5/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2021-29550?
Check the references section above for vendor advisories and patch information. Affected products include: Google Tensorflow.