CVE-2021-41219 : Exploit Details and Defense Strategies

TensorFlow is an open-source platform for machine learning that experienced vulnerabilities in sparse matrix multiplication due to undefined behavior through a

nullptr

reference binding.

Understanding CVE-2021-41219

In the affected versions of TensorFlow, issues arise when attempting sparse matrix multiplication, potentially leading to heap out-of-bounds access.

What is CVE-2021-41219?

TensorFlow versions including 2.6.0 to less than 2.6.1, 2.5.0 to less than 2.5.2, and below 2.4.4 are susceptible to undefined behavior via

nullptr

binding in sparse matrix multiplication.

The Impact of CVE-2021-41219

The vulnerability has a CVSS base score of 7.8, with high confidentiality, integrity, and availability impacts. It requires low privileges and no user interaction, making it a serious threat.

Technical Details of CVE-2021-41219

In-depth insights into the vulnerability and affected systems.

Vulnerability Description

The issue stems from binding a reference to

nullptr

during sparse matrix operations, potentially leading to heap out-of-bounds access in certain scenarios.

Affected Systems and Versions

TensorFlow versions >= 2.6.0, < 2.6.1
TensorFlow versions >= 2.5.0, < 2.5.2
TensorFlow versions < 2.4.4

Exploitation Mechanism

The vulnerability arises when attempting sparse matrix operations with dimensions of

a

or

b

being 0 or less, leading to attempts to write to an empty tensor and consequent heap out-of-bounds access.

Mitigation and Prevention

Protective measures and actions to address the CVE-2021-41219.

Immediate Steps to Take

Update TensorFlow to version 2.7.0 when available
Apply the fix by cherrypicking the commit on affected versions

Long-Term Security Practices

Regularly update TensorFlow to the latest supported versions
Monitor security advisories and apply patches promptly

Patching and Updates

Ensure timely implementation of security patches and updates provided by TensorFlow to mitigate the vulnerabilities effectively.