CVE-2021-29591 Explained : Impact and Mitigation
Learn about CVE-2021-29591, a critical vulnerability in TensorFlow that could lead to a stack overflow due to looping TFLite subgraph. Understand the impact, affected versions, and mitigation steps.
TensorFlow, known for its machine learning capabilities, was found to have a vulnerability that could lead to stack overflow due to looping TFLite subgraph. Attackers could exploit this issue to craft models resulting in an infinite loop during evaluation. This loop could, in some instances, trigger a stack overflow due to excessive recursive calls.
Understanding CVE-2021-29591
This CVE pertains to a vulnerability in TensorFlow that allows attackers to create models causing infinite loops, potentially leading to a stack overflow.
What is CVE-2021-29591?
TensorFlow's TFlite graphs should not have loops between nodes. However, this vulnerability allows attackers to manipulate models, leading to infinite loops and potential stack overflow due to too many recursive calls.
The Impact of CVE-2021-29591
The impact of this vulnerability is rated as HIGH, with a CVSS base score of 7.3. It could result in the compromise of confidentiality and availability, while requiring low privileges and having a low integrity impact.
Technical Details of CVE-2021-29591
The vulnerability, identified as CWE-835, involves Loop with Unreachable Exit Condition ('Infinite Loop'). It affects TensorFlow versions < 2.1.4, >= 2.2.0 and < 2.2.3, >= 2.3.0 and < 2.3.3, and >= 2.4.0 and < 2.4.2.
Vulnerability Description
The issue arises from a lack of validation in TFlite graphs, allowing attackers to create malicious models causing infinite loops and potential stack overflow.
Affected Systems and Versions
TensorFlow versions affected include < 2.1.4, >= 2.2.0 and < 2.2.3, >= 2.3.0 and < 2.3.3, and >= 2.4.0 and < 2.4.2.
Exploitation Mechanism
Attackers can exploit this vulnerability by crafting models with looping TFlite subgraphs, resulting in infinite loops and potential stack overflow.
Mitigation and Prevention
To address CVE-2021-29591, immediate steps must be taken to secure affected systems and prevent exploitation.
Immediate Steps to Take
Users are advised to update TensorFlow to version 2.5.0, which includes the necessary fix. Additionally, patches have been released for versions 2.1.4, 2.2.3, 2.3.3, and 2.4.2.
Long-Term Security Practices
It is essential to regularly update software and follow security best practices to mitigate the risk of similar vulnerabilities in the future.
Patching and Updates
Ensure that TensorFlow is updated to the latest version (2.5.0) to eliminate the vulnerability and apply patches for older affected versions.