Coinhive BrowseAloud Plugin Vector

Coinhive is a JavaScript miner for the Monero Blockchain that can be embedded in a website. Users run the miner directly in their browser. In a recent campaign, a malicious party uploaded obfuscated Coinhive JavaScript code into the BrowseAloud plugin code repository. A user may install this plugin within their web application stack. The resulting action meant that any user visiting a compromised site would be mining Monero via their browser.

Exploitation

Stages

1. A remote collective or set of malicious users exploits the BrowseAloud server that contains the code for the widely used BrowseAloud plugin. The attackers upload obfuscated Java Script code for this cryptomining tool.
2. An unknowing user downloads the infected code from the BrowseAloud server, installing it within their web application stack.
3. A visitor to the user’s website requests a page.
4. The server response includes a file that contains the infected BrowseAloud code (with Coinhive obfuscated code).
5. The JavaScript executes in the visitor’s browser and begins to utilize their CPU to mine Monero.

Prerequisites

The attacker must be able to send crafted packets to the target system.

Alert Logic Coverage

Alert Logic® has evaluated its customer base for exposure to the exploit and has developed signatures for mitigating the threat depending on the security service in place.

The Network-Based Intrusion Detection System (IDS) has been updated with the new signatures for this exploit when detected via Alert Logic Threat Manager™. If this signature is detected, an incident is generated in the Alert Logic console.

Recommendations for Mitigation

To mitigate the vulnerability, upgrade to a non-vulnerable version of the plugin.