An aerial view shows the logo of Israeli cyber firm NSO Group at one of its branches in the Arava Desert, southern Israel July 22, 2021. Picture taken with a drone. REUTERS/Amir Cohen

The US Commerce Department added Israel’s NSO Group and Candiru to its trade blacklist on Wednesday, saying they sold spyware to foreign governments that used the equipment to target government officials, journalists and others.

Positive Technologies of Russia, and Computer Security Initiative Consultancy PTE. LTD, from Singapore, were also listed. The Department said they trafficked in cyber tools used to gain unauthorized access to computer networks.

The companies’ addition to the list, for engaging in activities contrary to US national security or foreign policy interests, means that exports to them from US counterparts are restricted. It for instance makes it far harder for US security researchers to sell them information about computer vulnerabilities.

In the past, the NSO Group and Candiru have been accused of selling hacking tools to authoritarian regimes. NSO says it only sells its products to law enforcement and intelligence agencies and takes steps to curb abuse.

An NSO spokesperson did not immediately respond to a request for comment. Contact information for Candiru was not available.

The Biden administration imposed sanctions on Positive Technologies, a Russian cybersecurity firm, this year for providing support to Russian security services. The company has denied any wrongdoing.

Spokespeople for Positive Technologies and Computer Security Initiative Consultancy PTE. LTD, also known as COSEINC, did not immediately respond to requests for comment.