MercadoPago Android App Information Disclosure

Advisory ID Internal

1. Advisory Information

Title: MercadoPago Android App Information Disclosure
Advisory ID: CORE-2014-0011
Date published: 2014-12-19
Date of last update: 2014-12-17
Vendors contacted: Mercadolibre
Release mode: Coordinated release

2. Vulnerability Information

Class: Information Exposure [CWE-200]
Remotely Exploitable: No
Locally Exploitable: Yes
CVE Name: CVE-2014-0996


3. Vulnerability Description

With the MercadoPago application [1] you can complete the purchases you start from your computer directly from your cellphone in an easy way, under the same security standards that MercadoPagos's platform [2] offers and with the possibility to configure a security PIN.

The application logs sensitive user information using it. This includes user name, password, and access token obtained after authentication.

4. Vulnerable Packages

  • MercadoPago 1.2.5

Other versions could be also affected but were not tested.

5. Vendor Information, Solutions and Workarounds

MercadoLibre has updated their MercadoPago Android APP [1], so it's recommended that all the affected users update the app.

6. Credits

This vulnerability was discovered and researched by Nicolas Araujo from the Core Engineering Team. The publication of this advisory was coordinated by Joaquin Rodriguez Varela from Core Advisories Team.


7. Technical Description / Proof of Concept Code

This vulnerability can be exploited by third party applications that have permission to "READ_LOGS". Leveraging reading logs (achieved through the "logcat" command) third-party applications have access to sensitive information of users using the application of MercadoPago.

The application makes an abuse of "Log.i (...)" method allowing an information leak in HTTPS requests and response. You can see,in plain text, the log of HTTPS requests with the corresponding JSON message. This means, among other things, that the login username and password can be seen without problems.


Permits of "READ_LOGS" are no longer available for third-party applications since Android version 4.1. However, this still works for previous Android versions or for rooted devices.

Sample requests with visible sensitive information::

 12-02 14:43:15.370: I/MercadoPago Wallet(1762): makePostRequest(path: body: {"token":{"username":"[email protected]","client_secret":"wVOxSvl2a2D4Y5QLqAMgHV9x7PvI5oEl","client_id":"1311377052931992","grant_type":"password","password":"ContraseniaReSecreta"},"fingerprint":{"free_disk_space":154,"os":"android","vendor_ids":[{"value":"93e14342d9bd8e76","name":"android_id"},{"value":"28f2e34227c13a26","name":"fsuuid"}],"model":"sdk","ram":513800,"disk_space":197,"vendor_specific_attributes":{"platform":"armeabi-v7a","feature_nfc":false,"feature_flash":false,"feature_bluetooth":true,"feature_accelerometer":true,"feature_camera":true,"product":"sdk","feature_microphone":true,"feature_front_camera":false,"feature_touch_screen":true,"manufacturer":"unknown","device":"generic","brand":"generic","screen_density":0.75,"feature_gyroscope":false,"feature_compass":true,"feature_telephony":false,"feature_gps":false},"resolution":"240x284","system_version":"4.4.2"}} headers:null 12-02 14:43:19.320: I/MercadoPago Wallet(1762): makeGetRequest(path: 

Here is the code that makes the application leak this information:

 Class: # com.mercadopago.core.RestApi Methods: >> executePostRequest(String paramString, JSONObject paramJSONObject, Map<String, String> paramMap) Log.i("MercadoPago Wallet", "makePostRequest(path: " + paramString + " body: " + String.valueOf(paramJSONObject) + " headers:" + String.valueOf(paramMap)); ... >> makeDeleteRequest(String paramString, Map<String, String> paramMap) Log.i("MercadoPago Wallet", "makePostRequest(path: " + paramString + " headers:" + String.valueOf(paramMap)); ... >> makeGetRequest(String paramString) Log.i("MercadoPago Wallet", "makeGetRequest(path: " + paramString); ... 


8. Report Timeline

  • 2014-12-11: Core Security contacts Mercadolibre to inform them that a vulnerability has been found in their MercadoPago application for Android.
  • 2014-12-11: Mercadolibre sends their public PGP keys and request the technical information.
  • 2014-12-12: Core Security sends a draft advisory with technical details.
  • 2014-12-15: Mercadolibre informs they have corrected the problem and are about to release the new version of the MercadoPago APP to the PlayStore today. They request to delay the publication in order to give time to their users to update the APP.
  • 2014-12-15: Core Security schedules the release of the advisory for the 19th of December, 2014.
  • 2014-12-19: Advisory CORE-2014-0011 published.

9. References

[1] .
[2] .

10. About CoreLabs

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12. Disclaimer

The contents of this advisory are copyright (c) 2014 Core Security and (c) 2014 CoreLabs, and are licensed under a Creative Commons Attribution Non-Commercial Share-Alike 3.0 (United States) License: