CVE-2021-29549

Description

TensorFlow is an end-to-end open source platform for machine learning. An attacker can cause a runtime division by zero error and denial of service in `tf.raw_ops.QuantizedBatchNormWithGlobalNormalization`. This is because the implementation(https://github.com/tensorflow/tensorflow/blob/6f26b3f3418201479c264f2a02000880d8df151c/tensorflow/core/kernels/quantized_add_op.cc#L289-L295) computes a modulo operation without validating that the divisor is not zero. Since `vector_num_elements` is determined based on input shapes(https://github.com/tensorflow/tensorflow/blob/6f26b3f3418201479c264f2a02000880d8df151c/tensorflow/core/kernels/quantized_add_op.cc#L522-L544), a user can trigger scenarios where this quantity is 0. The fix will be included in TensorFlow 2.5.0. We will also cherrypick this commit on TensorFlow 2.4.2, TensorFlow 2.3.3, TensorFlow 2.2.3 and TensorFlow 2.1.4, as these are also affected and still in supported range.

How to fix CVE-2021-29549

To remediate CVE-2021-29549, upgrade the affected package to a fixed version below.

—upgrade to 2.1.4 or later
—upgrade to 2.1.4 or later
—upgrade to 744009c9e5cc5d0447f0dc39d055f917e1fd9e16 or later
—upgrade to 744009c9e5cc5d0447f0dc39d055f917e1fd9e16 or later
—upgrade to 2.1.4 or later
—upgrade to 744009c9e5cc5d0447f0dc39d055f917e1fd9e16 or later
—upgrade to 2.1.4 or later

Is CVE-2021-29549 being exploited?

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

Affected packages (7)

from 0, < 2.1.4, >= 2.2.0, < 2.2.3, >= 2.3.0, < 2.3.3, >= 2.4.0, < 2.4.2
from 0, < 2.1.4
from 0, < 744009c9e5cc5d0447f0dc39d055f917e1fd9e16 | from 0, < 2.2.0rc0, >= 2.2.0, < 2.3.0rc0, >= 2.3.0, < 2.3.4, >= 2.4.0, < 2.4.3
from 0, < 744009c9e5cc5d0447f0dc39d055f917e1fd9e16 | from 0, < 2.2.0rc0, >= 2.2.0, < 2.3.0rc0, >= 2.3.0, < 2.3.4, >= 2.4.0, < 2.4.3
from 0, < 2.1.4
from 0, < 744009c9e5cc5d0447f0dc39d055f917e1fd9e16 | from 0, < 2.2.0rc0, >= 2.2.0, < 2.3.0rc0, >= 2.3.0, < 2.3.4, >= 2.4.0, < 2.4.3
from 0, < 2.1.4

CVSS scores

Source	Version	Severity	Vector
osv	CVSS 4.0	—	CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N
osv	CVSS 3.1	LOW2.5	CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:L