WannaCry is a notorious ransomware that caused worldwide havoc in 2017 by encrypting files on infected Windows computers and demanding ransom payments in bitcoin to decrypt them. But does this vicious ransomware work on Mac computers?
The quick answer is no, WannaCry does not work natively on Mac OS. The WannaCry ransomware specifically targets vulnerabilities in older versions of Windows operating systems. It does not contain code to infect macOS devices.
However, that does not mean Mac users are completely immune to ransomware attacks. While the WannaCry strain itself will not infect Macs, threat actors have developed other ransomware variants that can target Apple devices. Mac users should still exercise caution and follow cybersecurity best practices.
How Does WannaCry Spread?
To understand why WannaCry does not impact Macs, it helps to know how this strain of ransomware propagates and infects Windows systems.
WannaCry contains worm-like capabilities that allow it to spread quickly across networks. It leverages an exploit called EternalBlue, which abuses functionality in Microsoft’s Server Message Block (SMB) protocol. EternalBlue gives WannaCry remote access to target systems.
From there, the ransomware looks for vulnerable Windows machines that have not installed a March 2017 Microsoft patch for the SMB exploits. When it finds an unpatched computer, WannaCry uses EternalBlue to inject malicious code and execute its ransomware payload.
The ransomware then encrypts files on the infected computer and any connected network shares or drives that are mapped to that system. It displays a ransom note demanding $300-$600 in bitcoin to decrypt the data.
WannaCry Targets Windows Vulnerabilities
WannaCry was specifically engineered to exploit Windows vulnerabilities. The EternalBlue SMB exploit only works against unpatched Windows machines, not macOS or Linux systems.
Apple uses its own proprietary SMB implementation called Apple Filing Protocol (AFP). This implementation is unaffected by EternalBlue and the vulnerabilities leveraged by WannaCry.
In addition, the ransomware payload relies on embedding itself in Windows processes and executing Windows commands. macOS running on Mac hardware has a completely different architecture from Windows and does not provide an environment WannaCry can execute in.
Essentially, WannaCry was designed to compromise Windows systems and does not have code to target or infect macOS. So while Windows PCs are at risk if left unpatched, Macs remain protected from this particular ransomware strain.
Other Ransomware Can Impact Macs
Although WannaCry itself does not function on Mac devices, it does not mean Macs are immune to ransomware in general. Cybercriminals have created other ransomware variants capable of encrypting Mac files for ransom.
Some examples of Mac-targeting ransomware include:
- EvilQuest – Discovered in 2020, this malware masquerades as a cracked version of a legit application. If installed, it encrypts files and demands payment.
- MacRansom – One of the earliest Mac ransomware strains, it encrypts files and appends .crypted extensions to them until payment is received.
- KeRanger – This ransomware was distributed trojanized versions of the Transmission BitTorrent client installer for Mac.
- FileCoder – Found in 2022, this variant pretends to be an update for Adobe Flash Player to bypass detection.
While less common than Windows ransomware, malicious actors continue to develop Mac-focused strains seeking profit. Mac users should be cognizant of this threat.
Recommended Security Tips for Mac Users
Here are some best practices Mac users should follow to minimize the risk of ransomware infections:
- Keep your Mac operating system and software up-to-date with the latest security patches.
- Use an antivirus program to detect potential malware threats.
- Never open attachments from unknown or suspicious senders.
- Back up your data regularly either locally or to the cloud.
- Avoid downloading software from unreputable sites; stick to official sources like the Mac App Store.
- Use the built-in Mac firewall to limit network access.
- Refrain from granting unnecessary permissions to apps you install.
Practicing these precautions will go a long way in keeping Macs safe from malware like ransomware.
Can Macs Get Infected Via Windows Files?
While native Mac ransomware exists, it is reasonable to wonder if Macs could get infected by handling Windows files already containing WannaCry or another Windows ransomware variant.
The short answer is no. Simply having an infected Windows file on your Mac does not pose a threat. The WannaCry code or other Windows ransomware payload has no way to execute in the macOS environment.
Even if you explicitly try to open a Windows ransomware file, it will not lead to infection. The Mac will likely warn that the file is unsupported or potentially malicious but cannot spread on the OS itself.
However, it is still wise to isolate any potentially infected Windows files. To be cautious, you may want to:
- Store Windows files with ransomware on a separate removable drive.
- Scan the files with a Windows anti-malware tool before further access.
- Delete the infected files if they are not needed.
Following this approach prevents any chance the infection could accidentally spread if the files are later accessed on a vulnerable Windows system.
Can Windows VMs on Macs Get Infected?
Mac users can run Windows in a virtual machine (VM) environment using software like Parallels or VMware Fusion. This allows Windows to execute in an isolated container on the Mac hardware.
Since these Windows VMs provide a full-fledged Windows environment, they can become infected with WannaCry or other Windows ransomware if unpatched and exposed.
For example, if you connected an unpatched Windows 10 VM directly to a network where WannaCry was active, the virtual machine could become compromised. The WannaCry malware would be able to encrypt any data accessible within the Windows VM.
However, WannaCry or other Windows malware in a Mac VM cannot escape the virtual environment to infect macOS itself or encrypt native Mac files external to the VM.
To avoid issues, make sure any Windows VMs are fully patched and security programs like antivirus are installed. Also isolate VMs from unfamiliar networks where malware could be present.
Can Apple Devices Get Malware?
Although Macs are generally less susceptible to malware like WannaCry, it does not mean Apple devices are 100% immune to all malicious software:
- iOS threats – Malicious or vulnerable apps in the iOS App Store can present risks. iOS jailbreaking also opens devices to malware.
- Mac adware – Some Mac tools bundled with adware or PUPs (potentially unwanted programs) can hijack browser data or insert unwanted ads.
- Cross-platform malware – Some threats target vulnerabilities in Java, Adobe apps, or other tools that exist across Windows, Mac, and Linux.
So while device-specific threats like WannaCry won’t impact Apple ecosystem, other common vectors exist that could allow malware to infect Macs, iPhones, or iPads.
Conclusion
In summary, the WannaCry ransomware strain does not work on Mac devices. It was engineered to explicitly target and encrypt vulnerable Windows computers. Macs do not contain the SMB vulnerabilities or Windows environment required for WannaCry to execute and propagate.
However, Macs are not immune to malware and ransomware as a whole. Other ransomware threats exist that can encrypt Mac files for ransom. And Windows malware could theoretically impact a virtual Windows machine running on a Mac.
By keeping OS and software updated, using security tools, and exercising caution, Mac users can help keep WannaCry and other ransomware threats at bay.