published March 20, 2025
⚡ A sneaky session fixation attack is possible with just a user account! An attacker can exploit the default cookie settings in open-webui version 0.3.8 to potentially hijack administrator sessions. 🔥 Think of it like leaving your front door slightly ajar while someone else has the key. An attacker can craft a malicious markdown image that, when viewed by an unsuspecting administrator, grants them access to the admin's session cookie, as if they're slipping right through your door! If an attacker successfully captures an admin's session cookie, they can stealthily take over the administrator account, leading to potential remote code execution (RCE). That's a nightmare scenario where an attacker could gain total control over your system and unleash chaos!
Think of it like leaving your front door slightly ajar while someone else has the key. An attacker can craft a malicious markdown image that, when viewed by an unsuspecting administrator, grants them access to the admin's session cookie, as if they're slipping right through your door! This vulnerability arises because open-webui sets the session cookie with `SameSite=Lax` and without the `Secure` flag, allowing it to be transmitted over unencrypted HTTP connections. An attacker can exploit this by embedding a malicious image in chat, which then sends the admin's session cookie to their server when viewed.
If an attacker successfully captures an admin's session cookie, they can stealthily take over the administrator account, leading to potential remote code execution (RCE). That's a nightmare scenario where an attacker could gain total control over your system and unleash chaos! To secure your system, upgrade to open-webui version 0.3.9 or later immediately. Additionally, implement proper cookie settings, ensuring cookies have the `Secure` flag enabled and are set to `SameSite=Strict` to prevent this type of attack. Regularly audit your security settings to keep vulnerabilities at bay. You've got this! By following these steps, you'll secure your application and keep those pesky attackers at bay! 🛡️