What is CVE-2021-37681?

CVE-2021-37681 is a high-severity vulnerability in Google Tensorflow, classified under NULL Pointer Dereference. CVSS score: 7.8/10. Published 2021-08-12.

How severe is CVE-2021-37681?

High severity. CVSS v3 base score is 7.8 out of 10.

NULL pointer dereference in Google Tensorflow

CVE-2021-37681

TensorFlow is an end-to-end open source platform for machine learning. In affected versions the implementation of SVDF in TFLite is [vulnerable to a null pointer error](https://github.com/tensorflow/tensorflow/blob/460e000de3a83278fb00b61a16d161b1964f15f4/tensorflow/lite/kernels/svdf.cc#L300-L313). The [`GetVariableInput` function](https://github.com/tensorflow/tensorflow/blob/460e000de3a83278fb00b61a16d161b1964f15f4/tensorflow/lite/kernels/kernel_util.cc#L115-L119) can return a null pointer but `GetTensorData` assumes that the argument is always a valid tensor. Furthermore, because `GetVariableInput` calls [`GetMutableInput`](https://github.com/tensorflow/tensorflow/blob/460e000de3a83278fb00b61a16d161b1964f15f4/tensorflow/lite/kernels/kernel_util.cc#L82-L90) which might return `nullptr`, the `tensor->is_variable` expression can also trigger a null pointer exception. We have patched the issue in GitHub commit 5b048e87e4e55990dae6b547add4dae59f4e1c76. 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.

Published 2021-08-12 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 7.8 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.002 (6.1th percentile), scored 2026-09-30.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 6th percentile — 6.1% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.002 · newest: 0.002 · change: 0.000

Affected products

Google Tensorflow — versions 2.5.0, 2.6.0
Tensorflow — versions >= 2.5.0, < 2.5.1, >= 2.4.0, < 2.4.3, < 2.3.4

Weakness classification (CWE)

CWE-476 — NULL Pointer Dereference

References

github.com/tensorflow/tensorflow/security/advisories/GHSA-7xwj-5r4v-429p (Third Party Advisory)
github.com/tensorflow/tensorflow/commit/5b048e87e4e55990dae6b547add4dae59f4e1c76 (Patch, Third Party Advisory)

Frequently asked questions

What is CVE-2021-37681?: CVE-2021-37681 is a high-severity vulnerability in Google Tensorflow, classified under NULL Pointer Dereference. CVSS score: 7.8/10. Published 2021-08-12.
How severe is CVE-2021-37681?: High severity. CVSS v3 base score is 7.8 out of 10.