The use of a suite of online tools that can make cyberattacks particularly difficult to defend against, appears to be part of an emerging censorship strategy that poses a serious transnational threat to press freedom and access to information.

When exiled Russian news website Meduza was hit with a flood of internet traffic in mid-April, it set off alarm bells among the staff as the deluge blocked publishing for more than four hours and briefly rendered the site inaccessible for some readers. It was the largest denial-of-service attack (DDoS) attack in Meduza's 10-year history.

"We were trying to spin up solutions... everything to continue to write news," Pavel Manylov, the site's lead software engineer, told the Committee to Protect Journalists (CPJ). "Our colleagues said the website was giving an error message and the content management system was not working properly. It was because of the enormous traffic, something new for us."

The scale wasn't the only notable thing about the attack. In their cyber assault, the attackers deployed a suite of online tools increasingly used to target media sites around the world, while keeping the perpetrators' identities secret.

To source and direct online traffic en masse, attackers often use a combination of these tools, including:

• Proxy providers offering access to IP addresses, which are unique numbers assigned to internet-connected devices;
• Other marketplaces where IP addresses are leased or resold; and
• Data centres that host and route online traffic.

Experts told CPJ...