CVE-2021-37669 Crash in NMS ops caused by integer conversion to unsigned in TensorFlow

What is CVE-2021-37669?

CVE-2021-37669 is a medium-severity vulnerability in Google Tensorflow, published on 12 Aug 2021. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

TensorFlow is an end-to-end open source platform for machine learning. In affected versions an attacker can cause denial of service in applications serving models using `tf.raw_ops.NonMaxSuppressionV5` by triggering a division by 0. The [implementation](https://github.com/tensorflow/tensorflow/blob/460e000de3a83278fb00b61a16d161b1964f15f4/tensorflow/core/kernels/image/non_max_suppression_op.cc#L170-L271) uses a user controlled argument to resize a `std::vector`. However, as `std::vector::resize` takes the size argument as a `size_t` and `output_size` is an `int`, there is an implicit conversion to unsigned. If the attacker supplies a negative value, this conversion results in a crash. A similar issue occurs in `CombinedNonMaxSuppression`. We have patched the issue in GitHub commit 3a7362750d5c372420aa8f0caf7bf5b5c3d0f52d and commit [b5cdbf12ffcaaffecf98f22a6be5a64bb96e4f58. The fix will be included in TensorFlow 2.6.0. We will also cherrypick this commit on TensorFlow 2.5.1, TensorFlow 2.4.3, and TensorFlow 2.3.4, as these are also affected and still in supported range.

Weakness: CWE-681

Which versions are affected by CVE-2021-37669?

22 open source packages ship an affected version, including tensorflow, tensorflow-cpu and tensorflow-gpu. It affects 1 product.

Products include Google Tensorflow.

How do I fix CVE-2021-37669?

Upgrade tensorflow to a fixed version for your release line: 2.3.4, 2.4.3 or 2.5.1.

Is CVE-2021-37669 being exploited?

There is no known exploitation of CVE-2021-37669 in the wild and no public exploit code.

Other vulnerabilities in Google Tensorflow

• CVE-2023-25668 TensorFlow vulnerable to heap out-of-buffer read in the QuantizeAndDequantize operation Critical 9.8
• CVE-2018-7575 Integer Overflow or Wraparound in Google TensorFlow Critical 9.8
• CVE-2021-37678 Arbitrary code execution due to YAML deserialization Critical 9.3
• CVE-2021-35958 Path traversal in n/a Critical 9.1
• CVE-2020-15202 Integer truncation in Shard API usage Critical 9.0

All Google Tensorflow vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as BIT-tensorflow-2021-37669, GHSA-vmjw-c2vp-p33c, PYSEC-2021-291, PYSEC-2021-582, PYSEC-2021-780.