CVE-2021-41224 : Exploit Details and Defense Strategies

TensorFlow is an open-source platform for machine learning. The vulnerability in affected versions allows triggering a heap out-of-bounds access in the implementation of

SparseFillEmptyRows

.

Understanding CVE-2021-41224

In this CVE, the TensorFlow platform is susceptible to a heap out-of-bounds read vulnerability affecting specific versions.

What is CVE-2021-41224?

The vulnerability in TensorFlow versions can be exploited when the size of

indices

does not align with the size of

values

, potentially leading to a heap out-of-bounds access.

The Impact of CVE-2021-41224

The vulnerability has a high base score of 7.1, posing a significant risk with high confidentiality impact and availability impact.

Technical Details of CVE-2021-41224

This section delves into the technical aspects of the vulnerability.

Vulnerability Description

The issue arises from the incorrect implementation of

SparseFillEmptyRows

, allowing for a heap out-of-bounds access.

Affected Systems and Versions

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

Exploitation Mechanism

The vulnerability occurs due to mismatches in the sizes of

indices

and

values

within the TensorFlow platform.

Mitigation and Prevention

Protecting systems from this vulnerability requires specific actions and practices.

Immediate Steps to Take

Update TensorFlow to version 2.7.0 to patch the vulnerability.
For versions still in the supported range (2.6.1, 2.5.2, and 2.4.4), apply the cherrypicked commit to address the issue.

Long-Term Security Practices

Regularly monitor and apply security updates for TensorFlow.
Conduct thorough code reviews to detect and prevent similar vulnerabilities.

Patching and Updates

Ensure timely application of patches and updates for TensorFlow to eliminate the vulnerability.