VDB-10628 · BID 62938 · OSVDB 98320

WhatsApp Messenger RC4 Encryption missing encryption

CVSS Meta Temp Score
CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.
Current Exploit Price (≈)
Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.
CTI Interest Score
Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
6.7$0-$5k0.00

A vulnerability was found in WhatsApp Messenger (Messaging Software) (affected version not known). It has been rated as critical. Affected by this issue is some unknown functionality of the component RC4 Encryption. The manipulation with an unknown input leads to a missing encryption vulnerability. Using CWE to declare the problem leads to CWE-311. The product does not encrypt sensitive or critical information before storage or transmission. Impacted is confidentiality, and integrity.

The weakness was presented 10/08/2013 by Thijs Alkemade with Adium as Piercing Through WhatsApp’s Encryption as not defined blog post (Website). The advisory is shared for download at blog.thijsalkema.de. The public release happened without coordination with the vendor. The exploitation is known to be difficult. The attack may be launched remotely. No form of authentication is required for exploitation. Technical details are unknown but a public exploit is available. The MITRE ATT&CK project declares the attack technique as T1600. The advisory points out:

As WhatsApp uses the same key for the incoming and the outgoing RC4 stream, we know that ciphertext byte i on the incoming stream xored with ciphertext byte i on the outgoing stream will be equal to xoring plaintext byte i on the incoming stream with plaintext byte i of the outgoing stream. By xoring this with either of the plaintext bytes, we can uncover the other byte.

A public exploit has been developed by Thijs Alkemade in Python and been published immediately after the advisory. The exploit is available at github.com. It is declared as proof-of-concept. The advisory illustrates:

The following is a Python script which can intercept messages to WhatsApp and which tries to decrypt the incoming messages by guessing all outgoing messages. It uses the WhatsApp library WhatsPoke for the FunXMPP parser. This does not work for the official WhatsApp client. It assumes the client logs in and sends only pings to the server. This was tested using yowsup-cli -l -d -c config -k from https://github.com/tgalal/yowsup. To use it with the official client, you would need to figure out which outgoing messages the real client sends and deal with the fact that they might contain data which is not as easy to predict, or even something more clever which can decrypt bytes in both streams using the other one.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

arstechnica.com is providing further details.

Productinfo

Type

Name

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB CVSS-B Score: 🔍
VulDB CVSS-BT Score: 🔍
VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.4
VulDB Meta Temp Score: 6.7

VulDB Base Score: 7.4
VulDB Temp Score: 6.7
VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
💳💳💳💳💳💳
💳💳💳💳💳💳
💳💳💳💳💳💳
VectorComplexityAuthenticationConfidentialityIntegrityAvailability
unlockunlockunlockunlockunlockunlock
unlockunlockunlockunlockunlockunlock
unlockunlockunlockunlockunlockunlock

VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

Exploitinginfo

Class: Missing encryption
CWE: CWE-311 / CWE-310
ATT&CK: T1600

Local: No
Remote: Yes

Availability: 🔍
Access: Public
Status: Proof-of-Concept
Author: Thijs Alkemade
Programming Language: 🔍
Download: 🔍
Price Prediction: 🔍
Current Price Estimation: 🔍

0-Dayunlockunlockunlockunlock
Todayunlockunlockunlockunlock

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔍
Exploit Delay Time: 🔍

Timelineinfo

10/08/2013 🔍
10/08/2013 +0 days 🔍
10/08/2013 +0 days 🔍
10/09/2013 +1 days 🔍
03/22/2019 +1990 days 🔍

Sourcesinfo

Advisory: Piercing Through WhatsApp’s Encryption
Researcher: Thijs Alkemade
Organization: Adium
Status: Not defined
SecurityFocus: 62938 - WhatsApp Information Disclosure Weakness
OSVDB: 98320

scip Labs: https://www.scip.ch/en/?labs.20161013
Misc.: 🔍

Entryinfo

Created: 10/09/2013 12:57
Updated: 03/22/2019 15:13
Changes: 10/09/2013 12:57 (52), 03/22/2019 15:13 (6)
Complete: 🔍

Discussion

No comments yet. Languages: en.

Please log in to comment.

Do you know our Splunk app?

Download it now for free!