PT-2026-65520 · Sdelements · Lets-Chat

Theodosis Paidakis · CVE-2026-66750 · Published 2026-07-28 · Updated 2026-07-28

NVD

CVSS v3.1

4.3

Medium

Base vector

AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N

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.

Exploit

Fix

Missing Authorization

Weakness Enumeration

CWE-862

Related Identifiers

CVE-2026-66750

Affected Products

Lets-Chat

References · 3

• 🔥 https://github.com/theopaid/Insufficient-Access-Controls-Allow-for-Unauthorized-File-Downloads-Let-s-Chat- · Exploit
• https://nvd.nist.gov/vuln/detail/CVE-2026-66750 · Security Note
• https://vulncheck.com/advisories/let-s-chat-broken-access-control-file-disclosure-via-get-files-route · Note