Critical · published February 6, 2026
🚨 A critical flaw in SandboxJS can let attackers escape the sandbox and run their own code! Imagine a playroom where the rules are suddenly ignored. 🔥 Think of SandboxJS like a secure playroom designed to keep kids (or code) safe. But if someone finds a way to change the rules of the game, they could easily slip out and wreak havoc in the rest of the house! This vulnerability allows attackers to potentially bypass security measures and execute arbitrary JavaScript outside of the designated sandbox. If exploited, it could lead to unauthorized access to sensitive data or the entire application being compromised. This is absolutely devastating!
Think of SandboxJS like a secure playroom designed to keep kids (or code) safe. But if someone finds a way to change the rules of the game, they could easily slip out and wreak havoc in the rest of the house! Prior to version 0.8.29, the prototype of Map was accessible within the SandboxJS environment, allowing attackers to overwrite `Map.prototype.has` and effectively escape the confines of the sandbox.
This vulnerability allows attackers to potentially bypass security measures and execute arbitrary JavaScript outside of the designated sandbox. If exploited, it could lead to unauthorized access to sensitive data or the entire application being compromised. This is absolutely devastating! Immediately update SandboxJS to version 0.8.29 or later to close this critical vulnerability. Additionally, review your application for any instances where the sandbox might be used to ensure there are no other potential security holes. Keep your code in a tight ship! You've got this! With that update, you'll have those security walls reinforced in no time! 🛡️