CVE-2026-66750

medium

Description

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.

References

https://www.vulncheck.com/advisories/let-s-chat-broken-access-control-file-disclosure-via-get-files-route

https://github.com/theopaid/Insufficient-Access-Controls-Allow-for-Unauthorized-File-Downloads-Let-s-Chat-

Details

Source: Mitre, NVD

Published: 2026-07-28

Updated: 2026-07-28

Risk Information

CVSS v2

Base Score: 4

Vector: CVSS2#AV:N/AC:L/Au:S/C:P/I:N/A:N

Severity: Medium

CVSS v3

Base Score: 4.3

Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N

Severity: Medium

CVSS v4

Base Score: 5.3

Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N

Severity: Medium