Data Leak Site.

What is a data leak site?

A data leak site is a website where attackers publish data they stole from a victim. It is used as pressure on victims who do not pay. MITRE ATT&CK says adversaries may use dedicated leak sites to distribute victim data.

How does a data leak site work?

MITRE ATT&CK describes the extortion pattern in its Financial Theft technique. An adversary demands payment from a victim after data is encrypted and exfiltrated. Exfiltration means data is copied out of the victim network. The adversary then threatens to leak the sensitive data to the public unless payment is made.

CISA describes the same pressure in its ransomware guide. It says some actors have exfiltrated victim data and pressured victims to pay by threatening to release the stolen data. CISA calls the use of both tactics, encryption and data theft, “double extortion”. It also notes that actors may exfiltrate data and threaten to release it as their only form of extortion, without using ransomware.

What does a simple example look like?

This is a simple illustration, not a real case. A company finds that its files are locked and that internal documents were copied out. The attackers say the documents will be shown on their website if the company does not pay. That website is the data leak site.

How can you detect or reduce the risk?

The leak site is the last step. The theft happens earlier, so the main defense is to notice data leaving the network. CISA lists potential signs of exfiltration for threat hunting, and one of them is an abnormal amount of data going out over any port. CISA also says common exfiltration tools include Rclone, Rsync, web-based file storage services and FTP or SFTP.

MITRE ATT&CK describes exfiltration over web services, where adversaries use legitimate external services that hosts already talk to. It lists two mitigations. Data loss prevention can detect and block sensitive data being uploaded to web services through browsers. Web proxies can enforce a policy that prevents use of unauthorized external services.

For storage that ransomware actors often target, CISA advises enabling delete protection or object lock, and considering version control. These steps help protect data from being deleted or overwritten.

How does it relate to nearby terms?

A data leak site is one way ransomware operators apply pressure. It is also linked to data breach, because the published material comes from stolen data. The dark web is a hidden part of the internet, covered on its own page. Related terms: ransomware, data-breach, dark-web, double-extortion.

Is a data leak site the same as a ransomware site?

No. A leak site is where stolen data is shown or offered. Ransomware is the malware that locks files. CISA says actors may threaten to release data even without using ransomware, so the two can be separate.

Is a data leak site the same as the dark web?

No. The dark web is a type of network space. A leak site is a purpose. MITRE ATT&CK only says adversaries use dedicated leak sites to distribute victim data.

Does paying stop the leak?

The sources we read do not say. CISA and MITRE ATT&CK describe the threat to release data, but they do not promise what happens after payment.

Brandefense can monitor the dark web for mentions of an organization’s data.

Stolen data can also be posted on open paste sites, which are public text sites and not run by the attackers.