Proofpoint recently noticed a disturbance in the ransomware force: The Necurs botnet, once one of the largest known botnets, has gone strangely quiet. It used to pump out hundreds of millions of malware-laden emails around the net, among other malicious actions such as distributed denial-of-service (DDoS) attacks.

Necurs is a P2P hybrid botnet that enables communication between infected computers and nodes that function as command-and-control (C&C) servers. The botnet has a domain generation algorithm that allows those infected machines to find a new C&C server should one go down. However, they have not been successful in this endeavor since the shutdown.

The Necurs Botnet Goes Dark

Anubis Networks was the first to observe the botnet’s inactivity on June 1. Millions of bots suddenly went silent, causing major disruptions in Dridex and Locky ransomware campaigns.

Anubis also discovered that an infected Necurs system would connect to a sinkhole only until the bot had found a C&C server to connect with. However, if the bot is somehow disconnected from that server, it might communicate with the sinkhole again.

Interestingly, the last time that Necurs went quiet for this long was in the fall of 2015, when a member of the Dridex gang was arrested in Cyprus, Softpedia reported.

What Does the Future Hold?

Will the Necurs botnet rise from the dead to deal electronic spam upon the unsuspecting masses once more? Proofpoint is doubtful because, although it’s not the first outage of its kind, “available data suggest that it involved a significant and ongoing failure of the C&C infrastructure behind the botnet.” That kind of damage could be hard to remedy.

Necurs needs these C&C servers to organize itself. Luckily, it seems that security researchers will be able to find indications if it does manage to acquire that necessary infrastructure, giving organizations warning as to the possible ransomware resurgence.

Though the email campaigns of Dridex and Locky are still out there, one can only hope the current trickle of Necurs-generated malware doesn’t turn into a flood in the future.

More from

Did Brazil DSL Modem Attacks Change Device Security?

From 2011 to 2012, millions of Internet users in Brazil fell victim to a massive attack against vulnerable DSL modems. By configuring the modems remotely, attackers could redirect users to malicious domain name system (DNS) servers. Victims trying to visit popular websites (Google, Facebook) were instead directed to imposter sites. These rogue sites then installed malware on victims' computers.According to a report from Kaspersky Lab Expert Fabio Assolini citing statistics from Brazil's Computer Emergency Response Team, the attack ultimately infected…

Who Carries the Weight of a Cyberattack?

Almost immediately after a company discovers a data breach, the finger-pointing begins. Who is to blame? Most often, it is the chief information security officer (CISO) or chief security officer (CSO) because protecting the network infrastructure is their job. Heck, it is even in their job title: they are the security officer. Security is their responsibility. But is that fair – or even right? After all, the most common sources of data breaches and other cyber incidents are situations caused…

Transitioning to Quantum-Safe Encryption

With their vast increase in computing power, quantum computers promise to revolutionize many fields. Artificial intelligence, medicine and space exploration all benefit from this technological leap — but that power is also a double-edged sword. The risk is that threat actors could abuse quantum computers to break the key cryptographic algorithms we depend upon for the safety of our digital world. This poses a threat to a wide range of critical areas. Fortunately, alternate cryptographic algorithms that are safe against…

Securing Your SAP Environments: Going Beyond Access Control

Many large businesses run SAP to manage their business operations and their customer relations. Security has become an increasingly critical priority due to the ongoing digitalization of society and the new opportunities that attackers exploit to achieve a system breach. Recent attacks related to corrupt data, stealing personal information and escalating privileges for remote code execution all highlight the new and varied entry points threat actors have taken advantage of. Attackers with the appropriate skills could be able to exploit…