CVE-2026-66749: Sdelements Lets-Chat

Medium severity, CVSS 6.5. EPSS: 0.4% chance of exploitation in the next 30 days.

Let's Chat 0.4.0 through 0.4.8 contains a null dereference vulnerability that allows authenticated attackers to crash the server by supplying a valid 24-character hex string room parameter that matches no document in the database. Attackers can send a crafted GET /messages request causing an uncaught TypeError in an asynchronous Mongoose callback that terminates the Node.js server process, with the same defect reachable through multiple code paths including the socket.io interface.

Affected products

• Sdelements Lets-Chat: from 0.4.0, up to and including 0.4.8

Published 2026-07-28. Last modified 2026-07-30.