Ryzerlo ransomware poses as Pokemon game (August 19, 2016)


The Dell SonicWall Threats Research team has received reports of a new Ransomware Trojan, Ryzerlo which encrypts the victim’s files and leaves an email address to be contacted to unlock victim’s files.

Infection cycle:

The Trojan comes across as Pokemon Go game with the icon:

It has the following properties:

Once the victim installs the executable, the trojan adds the following changes to the registry:

The Trojan adds two autostart objects to enable startup after reboot:

  • %APPDATA%RoamingMicrosoftWindowsStart MenuProgramsStartup[numbers].exe (copy of original) [Detected as GAV: Ryzerlo.A (Trojan)]

These executables have the following properties:

It tries to connect to the C&C server:

The trojan encrypts all the victims documents with extensions * .txt, * .rtf, * .doc, * .pdf, * .mht, * .docx, * .xls, * .xlsx, * .ppt, * .pptx, * .odt, * .jpg, *. png, * .csv, * .sql, * .mdb, * .sln, * .php, * .asp, * .aspx, * .html, * .xml, * .psd, * .htm, * .gif, * .png with .locked extension.

The trojan creates the following files on the victim’s desktop:

It displays the following details in the file pk (encryption key):

It displays the following ransom message in the file (Very important.txt in arabic):

This is in arabic which is translated as:

We urge our users to always be vigilant and cautious with any unsolicited attachments specially if you are not certain of the source.

SonicWALL Gateway AntiVirus provides protection against this threat via the following signature:

  • GAV: Ryzerlo.A (Trojan)
Security News
The SonicWall Capture Labs Threat Research Team gathers, analyzes and vets cross-vector threat information from the SonicWall Capture Threat network, consisting of global devices and resources, including more than 1 million security sensors in nearly 200 countries and territories. The research team identifies, analyzes, and mitigates critical vulnerabilities and malware daily through in-depth research, which drives protection for all SonicWall customers. In addition to safeguarding networks globally, the research team supports the larger threat intelligence community by releasing weekly deep technical analyses of the most critical threats to small businesses, providing critical knowledge that defenders need to protect their networks.