Connect with us

Hi, what are you looking for?



Researchers Downplay Size of Reaper IoT Botnet

The Mirai-like “Reaper” botnet that began infecting Internet of Things (IoT) devices in late September has only ensnared up to 20,000 bots so far, according to estimates from Arbor Networks.

The Mirai-like “Reaper” botnet that began infecting Internet of Things (IoT) devices in late September has only ensnared up to 20,000 bots so far, according to estimates from Arbor Networks.

Called Reaper, the botnet was said a couple of weeks ago to have infected over one million organizations worldwide, but Arbor claims that the actual size of the botnet fluctuates between 10,000 and 20,000 bots in total.

The botnet’s size, the researcher reveal, could change at any time. An additional 2 million hosts have been already identified by the botnet scanner as potential nodes, although they haven’t been ensnared into Reaper yet.

“At this time, it is not clear why these candidate bots have not been co-opted into the botnet. Possible explanations include: misidentification due to flaws in the scanning code, scalability/performance issues in the Reaper code injection infrastructure, or a deliberate decision by the Reaper botmasters to throttle back the propagation mechanism,” Arbor’s ASERT researchers note.

The botnet was likely created to launch distributed denial of service (DDoS) attacks and its operators are expected to offer it as a service for the intra-China DDoS-for-hire market. It can launch SYN-floods, ACK-floods, http floods, and DNS reflection/amplification attacks.

Reaper shows code similarities with Mirai, but isn’t considered a clone. While Mirai uses password cracking for infection, the new botnet exploits vulnerabilities in targeted IoT devices, Chinese security company Qihoo says.

The firm has discovered 9 vulnerability exploits integrated into the current samples, targeting devices from 7 different manufacturers, namely Dlink, Goahead, JAWS, Netgear, Vacron NVR, Linksys, and AVTECH. The exploits list is actively updated, with one targeting Vacron NVR that was added within two days after its public disclosure on October 8.

Advertisement. Scroll to continue reading.

“The botnet has embedded more than 100 DNS open resolvers in its LUA sample, so DNS amplification attack can be easily carried out. About one-third of these open DNS servers have been used as reflector in real DNS amplification attacks. We have yet to see this type of config in any other Mirai variants,” Qihoo notes.

The Chinese company also discovered that the botnet is using four different IPs for command and control (C&C), each serving a different purpose: downloader, controller, reporter, and loader. At the time of analysis, the researchers hadn’t seen a DDoS attack command issued, despite the necessary code to support such commands being present in the source file.

“The only instructions we saw are to download samples. This means the attacker is still focusing on spreading the botnets,” the researchers concluded.

Related: New Mirai-Linked IoT Botnet Emerges

Related: DDoS Threat Increases While Mirai Becomes ‘Pay-for-Play’

Written By

Ionut Arghire is an international correspondent for SecurityWeek.

Click to comment

Daily Briefing Newsletter

Subscribe to the SecurityWeek Email Briefing to stay informed on the latest threats, trends, and technology, along with insightful columns from industry experts.

SecurityWeek’s Threat Detection and Incident Response Summit brings together security practitioners from around the world to share war stories on breaches, APT attacks and threat intelligence.


Securityweek’s CISO Forum will address issues and challenges that are top of mind for today’s security leaders and what the future looks like as chief defenders of the enterprise.


Expert Insights

Related Content


The changing nature of what we still generally call ransomware will continue through 2023, driven by three primary conditions.


Luxury retailer Neiman Marcus Group informed some customers last week that their online accounts had been breached by hackers.


As it evolves, web3 will contain and increase all the security issues of web2 – and perhaps add a few more.


A recently disclosed vBulletin vulnerability, which had a zero-day status for roughly two days last week, was exploited in a hacker attack targeting the...


Satellite TV giant Dish Network confirmed that a recent outage was the result of a cyberattack and admitted that data was stolen.


Zendesk is informing customers about a data breach that started with an SMS phishing campaign targeting the company’s employees.

Artificial Intelligence

The release of OpenAI’s ChatGPT in late 2022 has demonstrated the potential of AI for both good and bad.

Artificial Intelligence

The degree of danger that may be introduced when adversaries start to use AI as an effective weapon of attack rather than a tool...