PHP 5.6.36 contains three high-severity security vulnerabilities that could expose your website to serious attacks. These vulnerabilities affect image processing, character encoding, and LDAP authentication systems. If your website is still running this outdated version, you're at significant risk of data breaches, denial of service attacks, and unauthorized access.
Approximately 449 websites worldwide are currently running PHP 5.6.36, making them potential targets for cybercriminals. The vulnerabilities were discovered in 2018 and remain unpatched on legacy systems. This comprehensive guide will help you identify whether your site is affected and provide step-by-step instructions to secure your installation.
Don't wait for an attack to happen—vulnerable systems are actively exploited in the wild. By taking action today, you can protect your users' data and maintain your site's integrity.
PHP 5.6.36 is a server-side programming language that powers millions of websites. It's what runs behind the scenes to process user requests, handle databases, and generate the web pages you see in your browser. Think of it as the engine of your website—if the engine has problems, the entire vehicle won't run safely.
PHP 5.6 was released in 2014 and reached end-of-life in December 2018. Running outdated software versions is like leaving your front door unlocked—attackers actively search for these known vulnerabilities to gain unauthorized access. The version 5.6.36 specifically contains vulnerabilities in critical components that handle image uploads, text processing, and authentication systems.
4 CVEs found. The most critical are explained below.
PHP can crash when processing certain malformed image files, specifically JPEG photos with corrupted metadata. An attacker could upload a specially crafted image to your website to cause problems.
Impact: Your website could go offline or become unstable if someone uploads a malicious image file. This affects any functionality that reads image metadata automatically.
↗ View on NVDPHP can get stuck in an infinite loop when processing certain corrupted text files or data with invalid character encoding. This freezes the affected part of your website.
Impact: Your website may become slow or unresponsive if someone sends specially crafted text data. Your server resources get consumed and legitimate users experience delays.
↗ View on NVDIf your website connects to a company directory server (LDAP), a malicious server administrator could cause PHP to crash by sending corrupted responses. This is mainly a concern for enterprise websites.
Impact: Your website could crash if it queries a compromised or malicious directory server. This primarily affects businesses using corporate authentication systems.
↗ View on NVDWhen visitors request package files (.phar) that don't exist, PHP displays an error page that doesn't properly sanitize user input. An attacker can inject malicious code into this error page.
Impact: Attackers can trick visitors into running malicious scripts through error pages. This could steal customer data, passwords, or spread malware to your website visitors.
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Securing your website from PHP 5.6.36 vulnerabilities isn't optional—it's essential for protecting your business and users. The three high-severity CVEs in this version can lead to data theft, website defacement, and service outages. Upgrading to a modern PHP version eliminates these vulnerabilities entirely while improving your site's performance and security.
SiteRecipe.com makes it easy to identify and monitor security vulnerabilities across your entire web infrastructure. Our platform automatically detects outdated software versions, scans for known CVEs, and tracks your remediation progress. Start your free security assessment today and take the first step toward a truly secure website.
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