Cherry Blossom

Today, June 15th 2017, WikiLeaks publishes documents from the CherryBlossom project of the CIA that was developed and implemented with the help of the US nonprofit Stanford Research Institute (SRI International).

CherryBlossom provides a means of monitoring the Internet activity of and performing software exploits on Targets of interest. In particular, CherryBlossom is focused on compromising wireless networking devices, such as wireless routers and access points (APs), to achieve these goals. Such Wi-Fi devices are commonly used as part of the Internet infrastructure in private homes, public spaces (bars, hotels or airports), small and medium sized companies as well as enterprise offices. Therefore these devices are the ideal spot for "Man-In-The-Middle" attacks, as they can easily monitor, control and manipulate the Internet traffic of connected users. By altering the data stream between the user and Internet services, the infected device can inject malicious content into the stream to exploit vulnerabilities in applications or the operating system on the computer of the targeted user.

The wireless device itself is compromized by implanting a customized CherryBlossom firmware on it; some devices allow upgrading their firmware over a wireless link, so no physical access to the device is necessary for a successful infection. Once the new firmware on the device is flashed, the router or access point will become a so-called FlyTrap. A FlyTrap will beacon over the Internet to a Command & Control server referred to as the CherryTree. The beaconed information contains device status and security information that the CherryTree logs to a database. In response to this information, the CherryTree sends a Mission with operator-defined tasking. An operator can use CherryWeb, a browser-based user interface to view Flytrap status and security info, plan Mission tasking, view Mission-related data, and perform system administration tasks.

Missions may include tasking on Targets to monitor, actions/exploits to perform on a Target, and instructions on when and how to send the next beacon. Tasks for a Flytrap include (among others) the scan for email addresses, chat usernames, MAC addresses and VoIP numbers in passing network traffic to trigger additional actions, the copying of the full network traffic of a Target, the redirection of a Target’s browser (e.g., to Windex for browser exploitation) or the proxying of a Target’s network connections. FlyTrap can also setup VPN tunnels to a CherryBlossom-owned VPN server to give an operator access to clients on the Flytrap’s WLAN/LAN for further exploitation. When the Flytrap detects a Target, it will send an Alert to the CherryTree and commence any actions/exploits against the Target. The CherryTree logs Alerts to a database, and, potentially distributes Alert information to interested parties (via Catapult).