Critical · published February 9, 2021
🔥 A double extension in uploaded files could lead to an unexpected security nightmare! The ProBot bot for Discord may let attackers manipulate the "Send an image when a user joins the server" feature like a chef who forgets to check the recipe for allergens. ⚠️ Picture a restaurant where the chef accepts any dish that arrives without checking if it’s safe to serve. A file named 'welcome.html.jpg' could slip in unnoticed, potentially running harmful code instead of just displaying a friendly image! An attacker could exploit this flaw to send malicious content that executes when a new user joins, jeopardizing the safety of your server and its members. This could lead to unauthorized access or disruption, making it a matter of critical importance to address. It’s absolutely devastating if taken lightly!
Picture a restaurant where the chef accepts any dish that arrives without checking if it’s safe to serve. A file named 'welcome.html.jpg' could slip in unnoticed, potentially running harmful code instead of just displaying a friendly image! CVE-2021-26918 allows for double extensions in file uploads, where a file like 'welcome.html.jpg' could be interpreted as an executable HTML file due to improper handling of content types. The uploader service does not enforce strict validation, allowing attackers to interfere with intended features or cause undefined behaviors.
An attacker could exploit this flaw to send malicious content that executes when a new user joins, jeopardizing the safety of your server and its members. This could lead to unauthorized access or disruption, making it a matter of critical importance to address. It’s absolutely devastating if taken lightly! To remediate this issue, ensure that your file uploader validates file types strictly, rejecting any file with multiple extensions. Keep the ProBot bot updated and review your Discord server settings to mitigate risks. It's highly advisable to set rules that disallow file types that could be executed. You’ve got this! By taking these actions, you'll keep your server secure and protect your community! 🛡️