Cybercriminals can now use compromised Wi-Fi routers in cafes, airports hotels and other public places to infect Android smartphones with malware.
According to Kaspersky researchers, hackers are infecting systems with Wroba.o malware, which was originally used in a campaign called Roaming Mantis to target Android phones. This momth, it added the ability to change domain name system (DNS) functionality.
Roaming Mantis, a.k.a Shaoye, was first observed by Kaspersky in 2018. It uses malicious Android package (APK) files to control infected Android devices and steal device information. It also has a phishing option for iOS devices and crypto-mining capabilities for PCs. The name of the campaign is based on its propagation via smartphones roaming between Wi-Fi networks, potentially carrying and spreading the infection.
Kaspersky discovered that Roaming Mantis recently introduced a domain name system (DNS) changer functionality in Wroba.o (a.k.a Agent.eq, Moqhao, XLoader), the malware that was primarily used in the campaign. DNS changer is a malicious program that directs the device connected to a compromised Wi-Fi router to a server under the control of cybercriminals instead of a legitimate DNS server. On the malicious landing page, the potential victim is prompted to download malware that can control the device or steal credentials.
At the moment, the threat actor behind Roaming Mantis is exclusively targeting routers located in South Korea and manufactured by a popular South Korean network equipment vendor. To identify them, the new DNS changer functionality gets the router’s IP address and checks the router’s model, compromising targeted ones by overwriting the DNS settings. In December 2022, Kaspersky observed 508 malicious APKs downloads in the country.
An investigation of malicious landing pages found that attackers are also targeting other regions, using smishing instead of DNS changers. This technique employs text messages to spread malicious links that direct the victim to a malicious site to download malware onto the device or steal user info via a phishing website.
According to Kaspersky Security Network (KSN) statistics from September to December 2022, the highest detection rate of Wroba.o malware (Trojan-Dropper.AndroidOS.Wroba.o) was in France (54.4%), Japan (12.1%) and the U.S. (10.1%).
“When an infected smartphone connects to ‘healthy’ routers in various public places like cafes, bars, libraries, hotels, shopping malls, airports, or even homes, Wroba.o malware can compromise these routers and affect other connected devices as well.” says Suguru Ishimaru, senior security researcher at Kaspersky.
“The new DNS changer functionality can manage all device communications using the compromised Wi-Fi router, such as redirecting to malicious hosts and disabling updates of security products. We believe that this discovery is highly critical for the cybersecurity of Android devices because it is capable of being widely spread in the targeted regions.”
To read the full report on newly implemented DNS changer functionality, visit Securelist.com.
Kaspersky researchers recommend the following:
- Refer to your router’s user manual to verify that your DNS settings haven’t been tampered with or contact your ISP for support.
- Change the default login and password for the admin web interface of the router and regularly update your router’s firmware from the official source.
- Never install router firmware from third party sources. Avoid using third-party repositories for your Android devices.
- Further, always check browser and website addresses to ensure they are legitimate; look for signs such as https when asked to enter data.
- Consider installing a mobile security solution, such as special security solution, to protect your devices from these and other threats.