CVE-2026-48157
MediumCVSS 6.1Exploitation Probability (EPSS)
Low risk17th percentile - higher than 17% of all known CVEs
Summary
Slim is a PHP micro framework that enables users to write simple web applications and APIs. In versions 4.4.0 through 4.15, if an application uses HttpException::setTitle() and/or setDescription() to include untrusted/request-derived data, an attacker could inject arbitrary HTML/JavaScript that executes in the victim's browser.
Risk Assessment
This vulnerability may lead to XSS attacks, posing a risk of user data theft or session hijacking. Applications that do not implement proper safeguards are vulnerable to exploitation by attackers.
Recommendation
It is recommended to update applications to version 4.15.2 or avoid passing untrusted data to the setTitle() and setDescription() methods. Additionally, registering a custom error renderer that escapes the title and description is advisable.
Original NVD description (English source)
Slim is a PHP micro framework that enables users to write simple web applications and APIs. In versions 4.4.0 through 4.15, if an application uses HttpException::setTitle() and/or setDescription() to include untrusted/request-derived data in the error title or description (e.g. "No products found matching '{$query}'."), an attacker could inject arbitrary HTML/JavaScript that executes in the victim's browser when they encounter an HTML error page generated by Slim. The vulnerability is present even with displayErrorDetails = false as the unescaped title and description are rendered on this error path. Built-in exceptions (HttpNotFoundException, HttpBadRequestException, etc.) ship plain-text defaults, so a vanilla Slim app with no user code is not exploitable. Only applications that feed untrusted data into setTitle() and/or setDescription() are affected. The issue has been fixed in 4.15.2. If developers are unable to immediately update their applications, they can work around this issue by avoiding passing untrusted/request-derived data into HttpException::setTitle() and setDescription() and using static, plain-text error copy instead. They should also register a custom error renderer (an ErrorRendererInterface implementation, or a subclass of HtmlErrorRenderer that escapes the title and description) for the HTML media type.