CVE-2021-37681

Null pointer exception in TensorFlow Lite

Severity Score

7.8

*CVSS v3.1

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

*Multiple Sources

Exploited in Wild

*KEV

Decision

*SSVC

Descriptions

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.

TensorFlow es una plataforma de código abierto de extremo a extremo para el aprendizaje automático. En las versiones afectadas la implementación SVDF en TFLite es [vulnerable a un error de puntero null](https://github.com/tensorflow/tensorflow/blob/460e000de3a83278fb00b61a16d161b1964f15f4/tensorflow/lite/kernels/svdf.cc#L300-L313). La función ["GetVariableInput"](https://github.com/tensorflow/tensorflow/blob/460e000de3a83278fb00b61a16d161b1964f15f4/tensorflow/lite/kernels/kernel_util.cc#L115-L119) puede devolver un puntero null pero "GetTensorData" asume que el argumento es siempre un tensor válido. Además, como "GetVariableInput" llama a ["GetMutableInput"](https://github.com/tensorflow/tensorflow/blob/460e000de3a83278fb00b61a16d161b1964f15f4/tensorflow/lite/kernels/kernel_util.cc#L82-L90) que puede devolver "nullptr", la expresión "tensor-)is_variable" también puede desencadenar una excepción de puntero null. Hemos parcheado el problema en el commit 5b048e87e4e55990dae6b547add4dae59f4e1c76 de GitHub. La corrección será incluida en TensorFlow versión 2.6.0. También seleccionaremos este commit en TensorFlow versión 2.5.1, TensorFlow versión 2.4.3 y TensorFlow versión 2.3.4, ya que estos también están afectados y todavía están en el rango de soporte.

*Credits: N/A

Attack Vector

Local

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

Attack Vector

Local

Attack Complexity

Low

Authentication

None

Confidentiality

Partial

Integrity

Partial

Availability

Partial

* Common Vulnerability Scoring System

SSVC

Decision:-

Exploitation

Automatable

Tech. Impact

* Organization's Worst-case Scenario

Timeline

2021-07-29 CVE Reserved
2021-08-12 CVE Published
2023-03-08 EPSS Updated
2024-08-04 CVE Updated
---------- Exploited in Wild
---------- KEV Due Date
---------- First Exploit

CWE

CWE-476: NULL Pointer Dereference

CAPEC

References (2)

URL	Tag	Source
https://github.com/tensorflow/tensorflow/security/advisories/GHSA-7xwj-5r4v-429p	Third Party Advisory

URL	Date	SRC

URL	Date	SRC
https://github.com/tensorflow/tensorflow/commit/5b048e87e4e55990dae6b547add4dae59f4e1c76	2021-08-18

URL	Date	SRC

Affected Vendors, Products, and Versions

Vendor		Product				Version		Other		Status
Vendor	Product	Version	Other	Status	<-- -->	Vendor	Product	Version	Other	Status
Google Search vendor "Google"		Tensorflow Search vendor "Google" for product "Tensorflow"				>= 2.3.0 < 2.3.4 Search vendor "Google" for product "Tensorflow" and version " >= 2.3.0 < 2.3.4"		-		Affected
Google Search vendor "Google"		Tensorflow Search vendor "Google" for product "Tensorflow"				>= 2.4.0 < 2.4.3 Search vendor "Google" for product "Tensorflow" and version " >= 2.4.0 < 2.4.3"		-		Affected
Google Search vendor "Google"		Tensorflow Search vendor "Google" for product "Tensorflow"				2.5.0 Search vendor "Google" for product "Tensorflow" and version "2.5.0"		-		Affected
Google Search vendor "Google"		Tensorflow Search vendor "Google" for product "Tensorflow"				2.6.0 Search vendor "Google" for product "Tensorflow" and version "2.6.0"		rc0		Affected
Google Search vendor "Google"		Tensorflow Search vendor "Google" for product "Tensorflow"				2.6.0 Search vendor "Google" for product "Tensorflow" and version "2.6.0"		rc1		Affected
Google Search vendor "Google"		Tensorflow Search vendor "Google" for product "Tensorflow"				2.6.0 Search vendor "Google" for product "Tensorflow" and version "2.6.0"		rc2		Affected