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Think Mutual Bank Mobile Banking App for iPhone fails to properly validate SSL certificates

Vulnerability Note VU#276408

Original Release Date: 2017-05-04 | Last Revised: 2017-05-10


Think Mutual Bank mobile banking app for iOS, version 3.1.5 and earlier, fails to properly validate SSL certificates provided by HTTPS connections, which may enable an attacker to conduct man-in-the-middle (MITM) attacks.


CWE-295: Improper Certificate Validation - CVE-2017-3213

Think Mutual Bank mobile banking app for iOS fails to properly validate SSL certificates provided by HTTPS connections, which means that an attacker in the position to perform MITM attacks may be able to obtain sensitive account information such as login credentials.


An attacker on the same network as the iOS device may be able to view or modify network traffic that should have been protected by HTTPS, which may lead to the exposure of sensitive account information, including login credentials.


Apply an update

The vendor has released version 3.2.0 to address this issue. Users are encouraged to update to the latest release.

Do not use affected versions of the application

The features and services provided by the application are likely accessible via the Think Mutual Bank web site. By using a web browser to access those resources, you may avoid situations where SSL is not validated.

Avoid untrusted networks

Avoid using untrusted networks, including public WiFi. Using your device on an untrusted network increases the chance of falling victim to a MITM attack.

Vendor Information


Think Mutual Bank Affected

Updated:  May 02, 2017



Vendor Statement

We have not received a statement from the vendor.

Vendor Information

We are not aware of further vendor information regarding this vulnerability.

CVSS Metrics

Group Score Vector
Base 4.8 AV:A/AC:L/Au:N/C:P/I:P/A:N
Temporal 4.6 E:F/RL:U/RC:C
Environmental 4.5 CDP:ND/TD:ND/CR:ND/IR:ND/AR:ND



Thanks to Will Strafach of for reporting this vulnerability.

This document was written by Joel Land.

Other Information

CVE IDs: CVE-2017-3213
Date Public: 2017-05-04
Date First Published: 2017-05-04
Date Last Updated: 2017-05-10 16:29 UTC
Document Revision: 14

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