CVE-2021-37649 : Exploit Details and Defense Strategies

A vulnerability has been discovered in TensorFlow that can lead to a null pointer dereference in the

UncompressElement

function.

Understanding CVE-2021-37649

This CVE affects TensorFlow versions 2.3.4, 2.4.0 to 2.4.3, and 2.5.0 to 2.5.1, allowing for a null pointer dereference in a specific function.

What is CVE-2021-37649?

TensorFlow, an open-source machine learning platform, contains a vulnerability in the

tf.raw_ops.UncompressElement

code, which can trigger a null pointer dereference. This issue arises due to a lack of validation when obtaining and dereferencing a pointer from a

Variant

tensor.

The Impact of CVE-2021-37649

The vulnerability has a high impact severity based on the CVSS score of 7.7. It does not require any special privileges to exploit and can lead to high availability and integrity impact.

Technical Details of CVE-2021-37649

The vulnerability stems from the code implementation of

tf.raw_ops.UncompressElement

in TensorFlow. The issue allows a null pointer dereference, which can be exploited locally with low complexity.

Vulnerability Description

The vulnerability occurs when the code attempts to decompress a

CompressedElement

obtained from a

Variant

tensor without verifying its existence, leading to a null pointer.

Affected Systems and Versions

TensorFlow versions 2.3.4, 2.4.0 to 2.4.3, and 2.5.0 to 2.5.1 are susceptible to this vulnerability.

Exploitation Mechanism

Attackers can exploit this vulnerability by crafting malicious inputs to trigger the null pointer dereference in the affected TensorFlow versions.

Mitigation and Prevention

It is crucial to take immediate steps to address and mitigate the CVE-2021-37649 vulnerability in TensorFlow to ensure system security.

Immediate Steps to Take

Users are advised to update TensorFlow to version 2.6.0 to patch the vulnerability. For versions 2.5.0 to 2.5.1, 2.4.0 to 2.4.3, and 2.3.4, the fix is available by cherrypicking the specific commit.

Long-Term Security Practices

Incorporate secure coding practices, conduct regular security audits, and stay informed about software vulnerabilities to prevent similar issues in the future.

Patching and Updates

Regularly check for security updates from TensorFlow and apply patches promptly to address known vulnerabilities.