CVE-2020-15209 : Exploit Details and Defense Strategies

In tensorflow-lite before versions 1.15.4, 2.0.3, 2.1.2, 2.2.1, and 2.3.1, a crafted TFLite model can force a node to have as input a tensor backed by a

nullptr

buffer, leading to a null pointer dereference.

Understanding CVE-2020-15209

This CVE involves a vulnerability in tensorflow-lite that allows a crafted model to cause a null pointer dereference.

What is CVE-2020-15209?

A crafted TFLite model can manipulate a tensor to have a

nullptr

buffer, resulting in a null pointer dereference due to a buffer index change in the flatbuffer serialization.

The Impact of CVE-2020-15209

The vulnerability has a CVSS base score of 5.9, with high availability impact. It poses a medium severity risk with no confidentiality or integrity impact.

Technical Details of CVE-2020-15209

This section provides detailed technical information about the vulnerability.

Vulnerability Description

A crafted TFLite model can force a node to have a tensor with a

nullptr

buffer, leading to a null pointer dereference.

Affected Systems and Versions

TensorFlow versions < 1.15.4
TensorFlow versions >= 2.0.0, < 2.0.3
TensorFlow versions >= 2.1.0, < 2.1.2
TensorFlow versions >= 2.2.0, < 2.2.1
TensorFlow versions >= 2.3.0, < 2.3.1

Exploitation Mechanism

The vulnerability is exploited by changing a buffer index in the flatbuffer serialization to convert a read-only tensor to a read-write one, causing a null pointer dereference.

Mitigation and Prevention

Protect your systems from CVE-2020-15209 with the following measures.

Immediate Steps to Take

Apply the patches provided by TensorFlow in versions 1.15.4, 2.0.3, 2.1.2, 2.2.1, or 2.3.1.
Monitor TensorFlow security advisories for updates.

Long-Term Security Practices

Regularly update TensorFlow to the latest secure versions.
Implement secure coding practices to prevent similar vulnerabilities.
Conduct regular security audits and testing.
Educate developers on secure coding practices.

Patching and Updates

Ensure timely application of patches released by TensorFlow to address the vulnerability.