CVE-2026-66750

Let's Chat 0.3.0 through 0.4.8 contains a broken access control vulnerability that allows authenticated attackers to download file attachments from private and password-protected rooms they are not a member of by exploiting missing room membership checks in the file retrieval route. Attackers can enumerate adjacent MongoDB ObjectIds derived from a known file ID to recover files uploaded by other users, as the GET /files/:id/:name route in app/controllers/files.js only enforces login authentication without consulting room membership or the Room.canJoin check.

CVSS v3 4.3 MEDIUM

4.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/theopaid/Insufficient-Access-Controls-Allow-for-Unauthorized-File-Downloads-Let-s-Chat-
https://www.vulncheck.com/advisories/let-s-chat-broken-access-control-file-disclosure-via-get-files-route

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-2026-66750

Mitre link : CVE-2026-66750

CVE.ORG link : CVE-2026-66750

JSON object : View

Products Affected

No product.

CWE

CWE-862

Missing Authorization

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