CVE-2021-37635

Description

TensorFlow is an end-to-end open source platform for machine learning. In affected versions the implementation of sparse reduction operations in TensorFlow can trigger accesses outside of bounds of heap allocated data. The [implementation](https://github.com/tensorflow/tensorflow/blob/a1bc56203f21a5a4995311825ffaba7a670d7747/tensorflow/core/kernels/sparse_reduce_op.cc#L217-L228) fails to validate that each reduction group does not overflow and that each corresponding index does not point to outside the bounds of the input tensor. We have patched the issue in GitHub commit 87158f43f05f2720a374f3e6d22a7aaa3a33f750. 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-2021-37635

To remediate CVE-2021-37635, 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 87158f43f05f2720a374f3e6d22a7aaa3a33f750 or later
—upgrade to 87158f43f05f2720a374f3e6d22a7aaa3a33f750 or later
—upgrade to 2.3.4 or later
—upgrade to 87158f43f05f2720a374f3e6d22a7aaa3a33f750 or later
—upgrade to 2.3.4 or later

Is CVE-2021-37635 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, < 87158f43f05f2720a374f3e6d22a7aaa3a33f750 | >= 2.3.0, < 2.3.4, >= 2.4.0, < 2.4.3
from 0, < 87158f43f05f2720a374f3e6d22a7aaa3a33f750 | >= 2.3.0, < 2.3.4, >= 2.4.0, < 2.4.3
from 0, < 2.3.4
from 0, < 87158f43f05f2720a374f3e6d22a7aaa3a33f750 | >= 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:L/VA:H/SC:N/SI:N/SA:N
osv	CVSS 3.1	HIGH7.3	CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:H