CVE-2026-66749

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.

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/theopaid/Unchecked-Room-Lookup-Leads-to-Server-Crash-Let-s-Chat-
https://www.vulncheck.com/advisories/let-s-chat-denial-of-service-via-null-dereference-in-room-lookup

Configurations

No configuration.

History

28 Jul 2026, 16:20

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-07-28 16:20

Updated : 2026-07-30 16:41

NVD link : CVE-2026-66749

Mitre link : CVE-2026-66749

CVE.ORG link : CVE-2026-66749

JSON object : View

Products Affected

No product.

CWE

CWE-476

NULL Pointer Dereference

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