CVE-2021-37651

Description

TensorFlow is an end-to-end open source platform for machine learning. In affected versions the implementation for `tf.raw_ops.FractionalAvgPoolGrad` can be tricked into accessing data outside of bounds of heap allocated buffers. The [implementation](https://github.com/tensorflow/tensorflow/blob/f24faa153ad31a4b51578f8181d3aaab77a1ddeb/tensorflow/core/kernels/fractional_avg_pool_op.cc#L205) does not validate that the input tensor is non-empty. Thus, code constructs an empty `EigenDoubleMatrixMap` and then accesses this buffer with indices that are outside of the empty area. We have patched the issue in GitHub commit 0f931751fb20f565c4e94aa6df58d54a003cdb30. 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.

How to fix CVE-2021-37651

To remediate CVE-2021-37651, upgrade the affected package to a fixed version below.

—upgrade to 2.3.4 or later
—upgrade to 2.3.4 or later
—upgrade to 0f931751fb20f565c4e94aa6df58d54a003cdb30 or later
—upgrade to 0f931751fb20f565c4e94aa6df58d54a003cdb30 or later
—upgrade to 2.3.4 or later
—upgrade to 0f931751fb20f565c4e94aa6df58d54a003cdb30 or later
—upgrade to 2.3.4 or later

Is CVE-2021-37651 being exploited?

Low — EPSS is 0.0%, meaning exploitation activity has not been observed at scale.

Affected packages (7)

>= 2.3.0, < 2.3.4, >= 2.4.0, < 2.4.3, >= 2.5.0, < 2.5.1
from 0, < 2.3.4
from 0, < 0f931751fb20f565c4e94aa6df58d54a003cdb30 | >= 2.3.0, < 2.3.4, >= 2.4.0, < 2.4.3
from 0, < 0f931751fb20f565c4e94aa6df58d54a003cdb30 | >= 2.3.0, < 2.3.4, >= 2.4.0, < 2.4.3
from 0, < 2.3.4
from 0, < 0f931751fb20f565c4e94aa6df58d54a003cdb30 | >= 2.3.0, < 2.3.4, >= 2.4.0, < 2.4.3
from 0, < 2.3.4

CVSS scores

Source	Version	Severity	Vector
osv	CVSS 4.0	—	CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N
osv	CVSS 3.1	HIGH7.1	CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N