PHP 5.6.31 is an outdated version running on approximately 469 websites worldwide, and it contains seven documented security vulnerabilities that put your site at serious risk. Among these flaws is a critical buffer over-read vulnerability that can be exploited through untrusted data, along with five additional high-severity issues affecting core PHP functions. If your website is still running this version, you're leaving your data and your users vulnerable to cyberattacks.
This guide will help you understand the specific threats posed by PHP 5.6.31's vulnerabilities and provide you with a clear action plan to upgrade and secure your website. We'll walk you through identifying whether your site uses this version, understanding the risks, and implementing the necessary fixes to protect your digital assets.
PHP is a server-side programming language that powers the backend functionality of websites. It runs on your web server and processes requests from visitors, handling everything from user logins to database queries. Think of it as the engine that makes your website function—when visitors interact with your site, PHP is often working behind the scenes to make things happen.
PHP 5.6.31 was released in 2017 as a patch version meant to fix bugs and security issues in the PHP 5.6 line. However, this version contains seven known security flaws that cybercriminals can exploit. These vulnerabilities range from buffer overflows (where attackers overload the system with data) to denial of service attacks (where hackers intentionally crash your website). Running outdated PHP versions is one of the most common reasons websites get hacked, making this a critical priority for any website owner.
7 CVEs found. The most critical are explained below.
PHP has a flaw when processing serialized data (a common way to store complex information). An attacker could send specially crafted data that causes PHP to read memory it shouldn't access. This could expose sensitive information from your server.
Impact: Attackers could potentially steal sensitive data like passwords, API keys, or customer information stored in server memory.
↗ View on NVDPHP's configuration file parser has a memory safety flaw. If your website accepts configuration input from untrusted sources, an attacker could exploit this to crash your server or run malicious code.
Impact: Your website could go offline (denial of service) or attackers could gain control of your server to steal data or spread malware.
↗ View on NVDAttackers can send specially formatted requests with extremely long variable names to make PHP work excessively hard. Your server wastes CPU processing these requests instead of serving real customers.
Impact: Your website becomes slow or completely unresponsive, causing downtime and lost revenue while the attack continues.
↗ View on NVDPHP's WDDX data processor (used for exchanging complex data formats) has a memory management bug. Malicious XML data could crash your PHP interpreter and take your website offline.
Impact: Attackers can easily crash your website by sending specially crafted data, causing service interruptions and potential data loss.
↗ View on NVDPHP's encryption extension doesn't properly handle certain error conditions. This could cause the interpreter to crash during normal encryption operations used for secure communications.
Impact: Your website could crash unexpectedly during normal HTTPS/SSL operations, especially if you handle sensitive encrypted data.
↗ View on NVDPHP's date/time processing has a flaw when parsing certain date strings. Attackers can craft special date inputs to read unintended information from your server's memory.
Impact: Sensitive server memory could be leaked, potentially exposing passwords, tokens, or other confidential data used by your application.
↗ View on NVDShowing first 10 of 1. View all on NVD ↗
| CVE ID | Severity | Score | Published | Description |
|---|---|---|---|---|
| CVE-2017-7890 | MEDIUM | 6.5 | 2017-08-02 | The GIF decoding function gdImageCreateFromGifCtx in gd_gif_in.c in the GD Graphics Library (aka libgd), as used in PHP before 5.6.31 and 7.x before 7.1.7, does not zero colorMap … |
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PHP 5.6.31's seven vulnerabilities—especially the critical buffer over-read flaw and multiple denial of service vectors—represent a serious threat to your website's security and your visitors' data. The good news is that upgrading to a modern PHP version is straightforward and takes just minutes with proper planning. By following the steps outlined above, you can eliminate these vulnerabilities and significantly strengthen your site's defense against cyber threats.
Don't let your website become an easy target for hackers. Use SiteRecipe.com's security audit tools to scan your site for vulnerable versions, outdated plugins, and other security risks in real-time. Our platform continuously monitors your PHP version and alerts you instantly if you're running vulnerable code, ensuring you stay protected. Start your free security assessment today and take control of your website's safety.
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