CVE-2018-7584 : Exploit Details and Defense Strategies

Between PHP versions 5.6.33 and 7.2.2, a vulnerability exists where a stack-based buffer under-read occurs during the parsing of an HTTP response in the php_stream_url_wrap_http_ex function within the ext/standard/http_fopen_wrapper.c file, leading to the copying of a large string.

Understanding CVE-2018-7584

In PHP through 5.6.33, 7.0.x before 7.0.28, 7.1.x through 7.1.14, and 7.2.x through 7.2.2, a stack-based buffer under-read occurs while parsing an HTTP response in the php_stream_url_wrap_http_ex function in ext/standard/http_fopen_wrapper.c, resulting in copying a large string.

What is CVE-2018-7584?

The vulnerability in PHP versions 5.6.33 to 7.2.2 allows for a stack-based buffer under-read during HTTP response parsing, potentially leading to the copying of a large string.

The Impact of CVE-2018-7584

This vulnerability could be exploited by attackers to execute arbitrary code or cause a denial of service by crashing the PHP application.

Technical Details of CVE-2018-7584

Vulnerability Description

Stack-based buffer under-read in PHP versions 5.6.33 to 7.2.2
Occurs during parsing of HTTP response in php_stream_url_wrap_http_ex function

Affected Systems and Versions

PHP versions 5.6.33 to 7.2.2

Exploitation Mechanism

Attackers can craft malicious HTTP responses to trigger the buffer under-read
This can lead to copying of a large string and potential code execution

Mitigation and Prevention

Immediate Steps to Take

Update PHP to a patched version immediately
Monitor for any unusual PHP application behavior

Long-Term Security Practices

Regularly update PHP and other software components
Implement secure coding practices to prevent buffer under-read vulnerabilities

Patching and Updates

Apply the latest patches and updates provided by PHP to address this vulnerability