PHP User.ini Config Exposure Scanner

PHP is a widely-used open-source general-purpose scripting language that is especially suited for web development. It can be embedded into HTML and is commonly employed by server-side programmers for building dynamic websites and applications. Today, PHP is utilized by many web developers around the globe to create complex online platforms, applications, and services, making it an integral part of the web development ecosystem. By employing PHP, developers can streamline website functions, manage online content, and improve web database integrations. Whether for small blogs or huge e-commerce sites, PHP remains a key player in the toolkit of web development for handling server-side scripts with efficiency and versatility.

The vulnerability identified here involves the exposure of PHP's user.ini file. An exposed user.ini file can compromise server security by revealing sensitive data and configurations that should remain private. This type of exposure can stem from incorrect server configurations leading to weaknesses susceptible to exploitation. When a PHP user.ini file is accessible to unauthorized users, it leaves room for critical information leakage. Such exposure could result in the misconfiguration of PHP settings, built for runtime directives' customization, which could be leveraged by attackers to destabilize the server or execute malicious scripts.

In terms of technical specifics, the vulnerability is characterized by a lack of adequate protection for the user.ini file, which sits at the root directory of a PHP web application. By default, this file may incorrectly grant excess visibility to its configurations. Attackers may seek to access URLs such as "/user.ini" or "/.user.ini" to retrieve the file's contents. The content of a PHP user.ini file can expose various PHP directives, potentially displaying valuable intel to attackers trying to exploit the server environment. Such details could include opcache settings, any assertion statements, and possibly database connections through modules like mssql or oci8.

If exploited, this vulnerability could have several adverse effects on the affected servers. An attacker could glean information necessary for the subsequent elevation of privilege attacks, leading to unauthorized access and data theft. Exposure of the user.ini configuration also risks server integrity, enabling alterations that could degrade performance or escalate into full system compromise. Further, knowledge acquisition from this exposure might constitute the groundwork for executing arbitrary code or SQL injections, using accessed directives against server defenses.

REFERENCES

• https://github.com/detectify/ugly-duckling/blob/master/modules/crowdsourced/php-user-ini-disclosure.json