Malware descriptions

And Now, an MBR Ransomware

Today my colleague Vitaly Kamluk wrote about a new GpCode-like ransomware which encrypts user’s files with RSA-1024 and AES-256 crypto-algorithms. We’re continuing to investigate this malware and will notify you about our findings.

However, is not the only piece of ransomware we found today. We’ve just discovered a malware which overwrites the master boot record (MBR) and demands a ransom to retrieve a password and restore the original MBR. This malware is detected as Trojan-Ransom.Win32.Seftad.a and Trojan-Ransom.Boot.Seftad.a.

This ransomware is downloaded by

If Seftad.a was downloaded by and run, the victim’s PC is rebooted and the following message appears on the screen:

The victim does not know the ransomware password. So, after three incorrect attempts, the infected machine will reboot and the same message will appear on the screen.

The entered symbols will be read with int 16h and then the following procedure will calculate the value and compare it with 2 bytes hash:

Fortunately, the hard drives or files are not encrypted as the malware author claims. This ransomware only overwrites the original MBR with a malicious one:

The original MBR is saved in the fourth sector of the hard drive with the malware’s infection marker stored at 0x9FE:

If the victim browses the malware author’s website, he is asked to pay $100 using ‘Paysafecard’ or ‘Ukash’.

If you are infected by this malware do not visit the website. Use the password ‘aaaaaaciip’ (without quotes) to restore the original MBR. If the password doesn’t work, you can cure your MBR with Kaspersky Rescue Disk 10.

UPD: We’ve just found a new version of Trojan-Ransom.Win32.Seftad. Detection will be added as soon as possible. Use the password ‘aaaaadabia’ (without quotes) to restore the original MBR.

UPD2: Do not use ‘fixmbr’ utility in case you are infected with this trojan because it will not restore your partition table and you won’t be able to boot your OS. If you are infected and passwords are invalid plug in your hard drive to a working computer and use this free tool which will restore your MBR.

And Now, an MBR Ransomware

Your email address will not be published. Required fields are marked *



Operation TunnelSnake

A newly discovered rootkit that we dub ‘Moriya’ is used by an unknown actor to deploy passive backdoors on public facing servers, facilitating the creation of a covert C&C communication channel through which they can be silently controlled. The victims are located in Africa, South and South-East Asia.

APT trends report Q1 2021

This report highlights significant events related to advanced persistent threat (APT) activity observed in Q1 2021. The summaries are based on our threat intelligence research and provide a representative snapshot of what we have published and discussed in greater detail in our private APT reports.

The leap of a Cycldek-related threat actor

The investigation described in this article started with one such file which caught our attention due to the various improvements it brought to this well-known infection vector.

Subscribe to our weekly e-mails

The hottest research right in your inbox