High · published February 3, 2026
🚨 An arbitrary file upload vulnerability in the AddFont() function of FPDF allows attackers to upload malicious PHP files — think of it as a sneaky chef slipping a secret ingredient into a recipe that could ruin the whole dish! 🔥 Imagine a restaurant that lets anyone bring in their own ingredients without checking them. Now, picture a crafty chef slipping in spoiled food that could be served to unsuspecting diners — that's the risk with this flaw! An attacker could exploit this vulnerability to upload and execute arbitrary PHP code on the server. This means they could potentially compromise sensitive data, manipulate server settings, or disrupt service, leading to significant harm and loss.
Imagine a restaurant that lets anyone bring in their own ingredients without checking them. Now, picture a crafty chef slipping in spoiled food that could be served to unsuspecting diners — that's the risk with this flaw! The vulnerability lies in the AddFont() function of FPDF (v1.86 and earlier), which allows for arbitrary file uploads. This means attackers can upload crafted PHP files that the server would execute, leading to remote code execution.
An attacker could exploit this vulnerability to upload and execute arbitrary PHP code on the server. This means they could potentially compromise sensitive data, manipulate server settings, or disrupt service, leading to significant harm and loss. To protect your applications, upgrade to FPDF v1.87 or later immediately. Additionally, implement strict validation and filtering for file uploads to ensure only safe file types are allowed. Regularly audit your file upload functionality to catch any potential vulnerabilities early. You've got this! Follow the steps to tighten up your defenses and keep your applications safe. 🛡️