There are now three different strains of destructive malware that have been identified in cyberattacks against organizations in Ukraine, and IT security professionals should be aware of both, especially as cybersecurity experts expect a broader range of cyberattacks to target Western organizations as the U.S. and allies respond to the crisis.
Both strains of malware, dubbed HermeticWiper and IsaacWiper, targeted Ukrainian organizations both before and during the Russian invasion of the country, according to cybersecurity firm ESET.
HermeticWiper, along with HermeticWizard and HermeticRansom, targeted multiple organizations in Ukraine on Feb. 23, just hours before the invasion began. The malware wipes itself from disk by overwriting it sown file with random bytes to prevent the analysis of the wiper in a post-incident analysis according to ESET researchers.
The malware is propagated inside compromised local networks by a custom worm, which ESET named HermeticWizard.
According to ESET, HermeticWiper wipes the data, HermetWizard spreads the malware on the local network, and HermeticRansom acts as a decoy ransomware. Samples suggest that the attacks were planned for several months, the firm says.
PE compilation timestamps dating back to Dec. 28, 2021 and code-signing certificate issue date of April 13, 2021 suggests that threat actors had long been planning these destructive malware attacks, according to ESET.
As the Russian invasion of Ukraine began, another malware strain emerged, which ESET named IsaacWiper. It is currently unknown if it is linked to HermeticWiper or if it comes from the same threat actor.
Like HermeticWiper, the IsaacWiper actors were planning this for a long time, with the oldest PE complication timestamp being Oct. 19, 2021, meaning it may have been used in previous attacks.
ESET says IsaacWiper attackers used RemCom, a remote access tool, and possibly Impacket for movement inside the network.
Just days after deploying IsaacWiper, attackers dropped a new version with debug logs, indicating attackers were unable to wipe some of the targeted machines and added log messages to understand what was happening, ESET researchers say.
First detailed by Microsoft, WhisperGate is another destructive malware that first appeared on Ukrainian systems on Jan. 13, with victims spanning government, non-profit and IT sectors.
Microsoft says the malware is intended to be destructive and render targeted devices inoperable. It has two stages that corrupts a system’s master boot record, displays a fake ransomware note and encrypts files based on certain file extensions.
Even though a ransom note is displayed, the targeted data is destroyed and can’t be recovered.
IT firm Broadcom, the operators of Symantec, says there are some similarities between HermeticWiper and WhisperGate, particularly in that both were disguised as ransomware.
Destructive malware mitigations and best practices
According to the U.S. Cybersecurity and Infrastructure Security Agency (CISA), there is a wide range of possible distribution vectors, including enterprise applications and IT management tools, centralized storage devices and network devices.
At the least, organizations should take these steps to help prevent intrusion and a method for malware distribution as these kinds of destructive malware attacks stemming from the Ukraine crisis are likely to make their way West, per CISA:
- Enable multifactor authentication
- Set antivirus and antimalware programs to conduct regular scans
- Enable strong email filters to prevent phishing emails
- Update software and patch systems
- Filter network traffic
More resources on these malware strains: