CVE-2019-16143 : Security Advisory and Response

A problem was found in the Rust blake2 crate prior to version 0.8.1. The BLAKE2b and BLAKE2s algorithms, when combined with HMAC, generate incorrect outputs due to their block sizes being half of what is required.

Understanding CVE-2019-16143

An issue was discovered in the blake2 crate before 0.8.1 for Rust. The BLAKE2b and BLAKE2s algorithms, when used with HMAC, produce incorrect results because the block sizes are half of the required sizes.

What is CVE-2019-16143?

This CVE identifies a vulnerability in the Rust blake2 crate versions prior to 0.8.1, affecting the BLAKE2b and BLAKE2s algorithms when used with HMAC.

The Impact of CVE-2019-16143

The vulnerability can lead to the generation of incorrect outputs due to inadequate block sizes, potentially compromising data integrity and security.

Technical Details of CVE-2019-16143

The technical aspects of the CVE are as follows:

Vulnerability Description

The issue arises from the incorrect output generated by the BLAKE2b and BLAKE2s algorithms when combined with HMAC due to undersized block sizes.

Affected Systems and Versions

Product: Not applicable
Vendor: Not applicable
Versions affected: All versions prior to 0.8.1

Exploitation Mechanism

The vulnerability can be exploited by crafting specific inputs to trigger the incorrect output generation in the affected algorithms.

Mitigation and Prevention

To address CVE-2019-16143, consider the following steps:

Immediate Steps to Take

Upgrade to version 0.8.1 or later of the Rust blake2 crate to mitigate the vulnerability.
Monitor for any unusual activities that might indicate exploitation of the issue.

Long-Term Security Practices

Regularly update software components to ensure the latest security patches are applied.
Implement secure coding practices to prevent similar vulnerabilities in the future.

Patching and Updates

Stay informed about security advisories and promptly apply patches released by the Rust community to address known vulnerabilities.