CVE-2021-28031 Explained : Impact and Mitigation

An issue was discovered in the scratchpad crate before 1.3.1 for Rust where the move_elements function can lead to a double-free vulnerability when a panic occurs in a user-provided f function.

Understanding CVE-2021-28031

This CVE details a vulnerability in the scratchpad crate for Rust that can result in a double-free scenario, potentially leading to further exploitation.

What is CVE-2021-28031?

CVE-2021-28031 highlights an issue in the move_elements function within the scratchpad crate before version 1.3.1 for Rust. This bug may trigger a double-free vulnerability upon a panic in a particular user-provided function.

The Impact of CVE-2021-28031

The impact of this vulnerability is significant as it can be exploited to execute arbitrary code or cause a denial of service (DoS) condition, posing a risk to the integrity and availability of affected systems.

Technical Details of CVE-2021-28031

This section covers the specific technical aspects of the CVE in terms of vulnerability description, affected systems and versions, as well as the exploitation mechanism.

Vulnerability Description

The vulnerability arises from the mishandling of memory in the move_elements function, leading to a double-free scenario upon specific conditions involving a panic in a user-provided f function.

Affected Systems and Versions

The vulnerability impacts the scratchpad crate versions prior to 1.3.1 for Rust, making systems with this library vulnerable to exploitation.

Exploitation Mechanism

Exploiting CVE-2021-28031 involves triggering a panic in the user-provided f function, which can cause the move_elements function to double-free memory, potentially leading to code execution or DoS.

Mitigation and Prevention

In this section, we outline the steps to mitigate the risks posed by CVE-2021-28031 and prevent potential exploitation.

Immediate Steps to Take

Users are advised to update the scratchpad crate to version 1.3.1 or higher to eliminate the vulnerability and prevent any possible exploitation of the double-free issue.

Long-Term Security Practices

Implementing secure coding practices, such as proper error handling and memory management, can help reduce the likelihood of similar vulnerabilities in the future.

Patching and Updates

Regularly checking for updates and applying patches promptly is crucial to maintaining the security of software dependencies and protecting systems from known vulnerabilities.