CVE-2019-19246 Explained : Impact and Mitigation

A heap-based buffer over-read vulnerability has been discovered in Oniguruma up to version 6.9.3, affecting PHP 7.3.x and potentially other software products.

Understanding CVE-2019-19246

This CVE involves a specific vulnerability in the "str_lower_case_match" function within the "regexec.c" file.

What is CVE-2019-19246?

The vulnerability is a heap-based buffer over-read in Oniguruma up to version 6.9.3, impacting PHP 7.3.x and other related products.

The Impact of CVE-2019-19246

The vulnerability could potentially lead to information disclosure or denial of service if exploited by malicious actors.

Technical Details of CVE-2019-19246

Oniguruma through version 6.9.3 has a heap-based buffer over-read in the "str_lower_case_match" function within the "regexec.c" file.

Vulnerability Description

The vulnerability allows attackers to read beyond the allocated buffer, potentially exposing sensitive information.

Affected Systems and Versions

Oniguruma up to version 6.9.3
PHP 7.3.x

Exploitation Mechanism

Attackers can exploit this vulnerability by crafting a malicious input that triggers the buffer over-read in the affected function.

Mitigation and Prevention

It is crucial to take immediate steps to address and prevent exploitation of this vulnerability.

Immediate Steps to Take

Apply patches provided by the respective vendors promptly.
Monitor official sources for security advisories related to this vulnerability.

Long-Term Security Practices

Regularly update software and libraries to patched versions.
Conduct security assessments and audits to identify and mitigate similar vulnerabilities.
Implement secure coding practices to prevent buffer over-read vulnerabilities.

Patching and Updates

Update Oniguruma to version 6.9.4 or later to mitigate the heap-based buffer over-read vulnerability.
Ensure PHP 7.3.x is updated to a patched version that addresses this specific issue.