What is CVE-2021-37687?

CVE-2021-37687 is a medium-severity vulnerability in Google Tensorflow, classified under Out-of-bounds Read. CVSS score: 5.5/10. Published 2021-08-12.

How severe is CVE-2021-37687?

Medium severity. CVSS v3 base score is 5.5 out of 10.

Out-of-bounds Read in Google Tensorflow

CVE-2021-37687

TensorFlow is an end-to-end open source platform for machine learning. In affected versions TFLite's [`GatherNd` implementation](https://github.com/tensorflow/tensorflow/blob/149562d49faa709ea80df1d99fc41d005b81082a/tensorflow/lite/kernels/gather_nd.cc#L124) does not support negative indices but there are no checks for this situation. Hence, an attacker can read arbitrary data from the heap by carefully crafting a model with negative values in `indices`. Similar issue exists in [`Gather` implementation](https://github.com/tensorflow/tensorflow/blob/149562d49faa709ea80df1d99fc41d005b81082a/tensorflow/lite/kernels/gather.cc). We have patched the issue in GitHub commits bb6a0383ed553c286f87ca88c207f6774d5c4a8f and eb921122119a6b6e470ee98b89e65d721663179d. 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.

Vulnerability class: Buffer Overflow

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

CVSS v3 metric

CVSS v3 base score 5.5 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N.

EPSS exploit prediction

EPSS: 0.002 (7.8th percentile), scored 2026-09-29.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 8th percentile — 7.8% 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-125 — Out-of-bounds Read

References

github.com/tensorflow/tensorflow/security/advisories/GHSA-jwf9-w5xm-f437 (Third Party Advisory)
github.com/tensorflow/tensorflow/commit/bb6a0383ed553c286f87ca88c207f6774d5c4a8f (Patch, Third Party Advisory)
github.com/tensorflow/tensorflow/commit/eb921122119a6b6e470ee98b89e65d721663179d (Third Party Advisory)

Frequently asked questions

What is CVE-2021-37687?: CVE-2021-37687 is a medium-severity vulnerability in Google Tensorflow, classified under Out-of-bounds Read. CVSS score: 5.5/10. Published 2021-08-12.
How severe is CVE-2021-37687?: Medium severity. CVSS v3 base score is 5.5 out of 10.