• Home
  • Cyber Crime
  • Cyber warfare
  • APT
  • Data Breach
  • Deep Web
  • Digital ID
  • Hacking
  • Hacktivism
  • Intelligence
  • Internet of Things
  • Laws and regulations
  • Malware
  • Mobile
  • Reports
  • Security
  • Social Networks
  • Terrorism
  • ICS-SCADA
  • POLICIES
  • Contact me
MUST READ

Critical WordPress Post SMTP plugin flaw exposes 200K+ sites to full takeover

 | 

Scattered Spider targets VMware ESXi in using social engineering

 | 

China-linked group Fire Ant exploits VMware and F5 flaws since early 2025

 | 

Allianz Life data breach exposed the data of most of its 1.4M customers

 | 

SECURITY AFFAIRS MALWARE NEWSLETTER ROUND 55

 | 

Security Affairs newsletter Round 534 by Pierluigi Paganini – INTERNATIONAL EDITION

 | 

Law enforcement operations seized BlackSuit ransomware gang’s darknet sites

 | 

Arizona woman sentenced for aiding North Korea in U.S. IT job fraud scheme

 | 

Operation CargoTalon targets Russia’s aerospace with EAGLET malware,

 | 

Unpatched flaw in EoL LG LNV5110R cameras lets hackers gain Admin access

 | 

Koske, a new AI-Generated Linux malware appears in the threat landscape

 | 

Mitel patches critical MiVoice MX-ONE Auth bypass flaw

 | 

Coyote malware is first-ever malware abusing Windows UI Automation

 | 

SonicWall fixed critical flaw in SMA 100 devices exploited in Overstep malware attacks

 | 

DSPM & AI Are Booming: $17.87B and $4.8T Markets by 2033

 | 

Stealth backdoor found in WordPress mu-Plugins folder

 | 

U.S. CISA adds CrushFTP, Google Chromium, and SysAid flaws to its Known Exploited Vulnerabilities catalog

 | 

U.S. CISA urges FCEB agencies to fix two Microsoft SharePoint flaws immediately and added them to its Known Exploited Vulnerabilities catalog

 | 

Sophos fixed two critical Sophos Firewall vulnerabilities

 | 

French Authorities confirm XSS.is admin arrested in Ukraine

 | 
  • Home
  • Cyber Crime
  • Cyber warfare
  • APT
  • Data Breach
  • Deep Web
  • Digital ID
  • Hacking
  • Hacktivism
  • Intelligence
  • Internet of Things
  • Laws and regulations
  • Malware
  • Mobile
  • Reports
  • Security
  • Social Networks
  • Terrorism
  • ICS-SCADA
  • POLICIES
  • Contact me
  • Home
  • Breaking News
  • Cyber Crime
  • Hacking
  • Malware
  • Microsoft details techniques of Mac ransomware

Microsoft details techniques of Mac ransomware

Pierluigi Paganini January 06, 2023

Microsoft warns of different ransomware families (KeRanger, FileCoder, MacRansom, and EvilQuest) targeting Apple macOS systems.

Microsoft Security Threat Intelligence team warns of four different ransomware families (KeRanger, FileCoder, MacRansom, and EvilQuest) that impact Apple macOS systems.

The initial vector in attacks involving Mac ransomware typically relies on user-assisted methods, such as downloading and running fake or weaponized applications. The ransomware can also be delivered as a second-stage payload dropper or part of a supply chain attack. 

The experts state that malware creators abuse legitimate functionalities and implement various techniques to exploit vulnerabilities, evade defenses, or trick users into infecting their devices.

One of the most important capabilities of ransomware is the capability of targeting specific files to encrypt. Microsoft researchers observed various techniques used by ransomware families to enumerate files and directories on Mac.

FileCoder and MacRansom use the Linux find utility to search for selected files to encrypt. 

The FileCoder ransomware, for example, searches the “/Users” and “/Volumes” directories by invoking the find command twice, using different paths to enumerate and excluding the README file while searching the “/Users” path.

mac ransomware

The researchers reported that KeRanger and EvilQuest use a sequence of opendir(), readdir(), and closedir() library functions to get the list of files.

The KeRanger, MacRansom, and EvilQuest ransomware families utilize a combination of hardware- and software-based checks to avoid being executed in a virtual environment for analysis and debugging purposes.

Hardware-based checks include checking a device’s hardware model (MacRansom), checking the logical and physical processors of a device (MacRansom), checking the MAC OUI of the device (EvilQuest), and checking the device’s CPU count and memory size (EvilQuest).

Code-related checks include delayed execution (KeRanger), PT_DENY_ATTACH (PTRACE) for an anti-debugging trick that prevents debuggers from attaching to the current malware process (EvilQuest and MacRansom), P_TRACED flag to check whether malware is being debugged (EvilQuest), and time-based check (EvilQuest).

Persistence is maintained by creating launch agents or launch daemons or using kernel queues.

“The ransomware families we analyzed often share similar anti-analysis and persistence techniques. However, these same ransomware families differ in encryption logic. Some use AES-RSA encryptions, while others use system utilities, XOR routine, or custom encryption logic to encrypt files. These encryption methods range from in-place modification to creating a new file while deleting the original one.” reads the analysis published by Microsoft. “Common among the ransomware observed is adding a new extension or simply encrypting the file without adding any new one.”

While FileCoder uses the ZIP utility to encrypt files, KeRanger uses AES encryption in Cipher block chaining (CBC) mode to encrypt files. MacRansom employes a symmetric algorithm for encrypting files and decrypting its ransom note “._README_”. 

EvilQuest also uses a custom symmetric key encryption routine to encrypt victims’ files.

The researchers observed two EvilQuest variants using two mechanisms of keylogging (T1056.001), the API CGEventTapCreate and the IOHIDManagerCreate API.

EvilQuest uses a set APIs (NSCreateObjectFileImageFromMemory, NSLinkModule, NSLookupSymbolInModule, NSAddressOfSymbol) to implement in-memory execution-

“Ransomware continues to be one of the most significant threats affecting any platform. Our analysis of ransomware on Mac operating systems shows how its creators use various techniques to remain hidden from automated analysis systems or make manual inspection by analysts challenging.” Microsoft concludes. “Understanding ransomware routines and their effects on any device or platform is essential for individual users to take steps toward device and data protection.”

Follow me on Twitter: @securityaffairs and Facebook and Mastodon

[adrotate banner=”9″][adrotate banner=”12″]

Pierluigi Paganini

(SecurityAffairs – hacking, Mac ransomware)

[adrotate banner=”5″]

[adrotate banner=”13″]


facebook linkedin twitter

Apple Cybercrime EvilQuest FileCoder Hacking hacking news information security news IT Information Security KeRanger macOS macransom malware Pierluigi Paganini Security Affairs Security News

you might also like

Pierluigi Paganini July 28, 2025
Critical WordPress Post SMTP plugin flaw exposes 200K+ sites to full takeover
Read more
Pierluigi Paganini July 28, 2025
Scattered Spider targets VMware ESXi in using social engineering
Read more

leave a comment

newsletter

Subscribe to my email list and stay
up-to-date!

    recent articles

    Critical WordPress Post SMTP plugin flaw exposes 200K+ sites to full takeover

    Security / July 28, 2025

    Scattered Spider targets VMware ESXi in using social engineering

    Cyber Crime / July 28, 2025

    China-linked group Fire Ant exploits VMware and F5 flaws since early 2025

    Hacking / July 28, 2025

    Allianz Life data breach exposed the data of most of its 1.4M customers

    Data Breach / July 27, 2025

    SECURITY AFFAIRS MALWARE NEWSLETTER ROUND 55

    Malware / July 27, 2025

    To contact me write an email to:

    Pierluigi Paganini :
    pierluigi.paganini@securityaffairs.co

    LEARN MORE

    QUICK LINKS

    • Home
    • Cyber Crime
    • Cyber warfare
    • APT
    • Data Breach
    • Deep Web
    • Digital ID
    • Hacking
    • Hacktivism
    • Intelligence
    • Internet of Things
    • Laws and regulations
    • Malware
    • Mobile
    • Reports
    • Security
    • Social Networks
    • Terrorism
    • ICS-SCADA
    • POLICIES
    • Contact me

    Copyright@securityaffairs 2024

    We use cookies on our website to give you the most relevant experience by remembering your preferences and repeat visits. By clicking “Accept All”, you consent to the use of ALL the cookies. However, you may visit "Cookie Settings" to provide a controlled consent.
    Cookie SettingsAccept All
    Manage consent

    Privacy Overview

    This website uses cookies to improve your experience while you navigate through the website. Out of these cookies, the cookies that are categorized as necessary are stored on your browser as they are essential for the working of basic functionalities...
    Necessary
    Always Enabled
    Necessary cookies are absolutely essential for the website to function properly. This category only includes cookies that ensures basic functionalities and security features of the website. These cookies do not store any personal information.
    Non-necessary
    Any cookies that may not be particularly necessary for the website to function and is used specifically to collect user personal data via analytics, ads, other embedded contents are termed as non-necessary cookies. It is mandatory to procure user consent prior to running these cookies on your website.
    SAVE & ACCEPT