QNAP NAS devices face fresh Deadbolt ransomware attack
The ransomware variant has returned to infect more than 1,000 QNAP devices


Deadbolt, a ransomware variant that attacked QNAP storage in January, is back and infecting more of the drives, researchers revealed this week.
Deadbolt is a ransomware variant first identified in January. It targets network-attached storage (NAS) devices from QNAP, which run the company's own Linux distribution called QTS.
Rather than encrypting the whole drive, Deadbolt concentrates on encrypting backup drives and then hacks the device's web interface to deliver a ransomware message.
Infections peaked on January 26, according to cyber security company Censys, affecting almost 5,000 of the 130,000 QNAP devices in use. QNAP force updated its firmware in January to stop the infections.
This update reportedly caused side effects including broken iSCSI connections. It also removed the hacked interface, which stopped hacked users who had paid the ransom from decrypting the files. However, Censys said that it reduced the number of infected devices at the time to under 300.
The ransomware resurged on QNAP devices this month. Censys saw new infections beginning on March 16, when the number of infected devices stood at 373. Within three days, the number of infected devices had grown to 1,146.
While the attackers are using a different Bitcoin address for the latest ransom demand, the rest of the attack remains the same, Censys said. They are demanding 0.03 bitcoins (currently worth around $1,280).
Sign up today and you will receive a free copy of our Future Focus 2025 report - the leading guidance on AI, cybersecurity and other IT challenges as per 700+ senior executives
RELATED RESOURCE
Identity is key to stopping these five cyber security attacks
Many attacks begin with the same weakness: user accounts
The attackers promise to deliver a decryption key in exchange for the ransom payment. They also make a separate offer to QNAP via the hacked web interface, offering it full details of the technical exploit that enabled the attack for five bitcoins ($213,300) or a master decryption key for 50 bitcoins ($2.13m).
This attack is unusual, in that aside from the hacked web interface, the attackers only communicate with the victims via bitcoin payments. They return the encryption key from a ransom payment in the OPRETURN field of a Bitcoin transaction.
QNAP drives have suffered attacks before, including infection by Dovecat crypto-mining malware and QSnatch, legacy malware which stopped administrators from applying security patches.
Danny Bradbury has been a print journalist specialising in technology since 1989 and a freelance writer since 1994. He has written for national publications on both sides of the Atlantic and has won awards for his investigative cybersecurity journalism work and his arts and culture writing.
Danny writes about many different technology issues for audiences ranging from consumers through to software developers and CIOs. He also ghostwrites articles for many C-suite business executives in the technology sector and has worked as a presenter for multiple webinars and podcasts.
-
Prolific ransomware operator added to Europe’s Most Wanted list as US dangles $10 million reward
News The US Department of Justice is offering a reward of up to $10 million for information leading to the arrest of Volodymyr Viktorovych Tymoshchuk, an alleged ransomware criminal.
-
Jaguar Land Rover “did the right thing” shutting down systems to thwart cyber attack
News The attack on Jaguar Land Rover highlights the growing attractiveness of the automotive sector
-
Ransomware attack on IT supplier disrupts hundreds of Swedish municipalities
News The attack on IT systems supplier Miljödata has impacted public sector services across the country
-
A notorious hacker group is ramping up cloud-based ransomware attacks
News The Storm-0501 threat group is refining its tactics, according to Microsoft, shifting away from traditional endpoint-based attacks and toward cloud-based ransomware.
-
Security researchers have just identified what could be the first ‘AI-powered’ ransomware strain – and it uses OpenAI’s gpt-oss-20b model
News Using OpenAI's gpt-oss:20b model, ‘PromptLock’ generates malicious Lua scripts via the Ollama API.
-
Data I/O shuts down systems in wake of ransomware attack
News Regulatory filings by Data I/O suggest the costs of dealing with the attack could be significant
-
Average ransom payment doubles in a single quarter
News Targeted social engineering and data exfiltration have become the biggest tactics as three major ransomware groups dominate
-
BlackSuit ransomware gang taken down in latest law enforcement sting – but members have already formed a new group
News The notorious gang has seen its servers taken down and bitcoin seized, but may have morphed into a new group called Chaos