In May 2025, cybersecurity researchers identified a sophisticated macOS information stealer named ‘AppleProcessHub.’ This malware employs advanced techniques to infiltrate systems, exfiltrate sensitive data, and communicate with its command-and-control (C2) infrastructure.
Discovery and Initial Analysis
On May 15, 2025, the MalwareHunterTeam detected a suspicious file named libsystd.dylib. Despite its .dylib extension, which typically denotes a dynamic library, this file was an executable targeting the x86_64 architecture. Its low detection rates across antivirus platforms raised immediate concerns.
Further examination revealed that ‘AppleProcessHub’ targets various sensitive data, including:
– Shell Histories: Bash and zsh command histories, which can reveal user activities and credentials.
– Configuration Files: GitHub and SSH configurations, potentially exposing repository access and secure shell connections.
– Keychain Database: macOS’s secure storage for passwords and certificates, providing access to a wide range of user credentials.
The extraction of such data poses significant risks, from personal information theft to potential breaches of organizational networks.
Attack Mechanism
‘AppleProcessHub’ operates through a two-stage attack process:
1. Initial Execution: The primary Mach-O binary initiates contact with the C2 server at appleprocesshub[.]com.
2. Payload Delivery: The server responds by delivering a second-stage bash script, which executes further malicious activities.
This method allows the malware to maintain a minimal footprint initially, reducing the likelihood of detection.
Evasion Techniques
The malware employs several sophisticated evasion strategies:
– String Obfuscation: Critical strings within the code are encrypted using AES-128 in ECB mode, complicating static analysis.
– Dynamic Function Calls: Indirect function calls are used to hinder reverse engineering efforts.
– Asynchronous Execution: Utilizing Grand Central Dispatch, the malware executes tasks asynchronously, enhancing performance and stealth.
Command-and-Control Communication
A notable aspect of ‘AppleProcessHub’ is its encrypted communication with the C2 server. The malware decrypts base64-encoded strings to reconstruct the C2 URL:
– Base64 Strings:
– umm8pChcGqXHmKhPKLz7AQ==
– WnD1BYMsv1hA87nbaMRsyA==
– fg94nzBafSnFOdSgX+4Lz0Mqgem4m+H1ji0fIoVRuDI=
– Decryption Key: CMKD378491212qwe
When decrypted, these strings form the complete C2 endpoint URL:
– https://www.appleprocesshub[.]com/v1/resource
This method ensures that the C2 details remain concealed until runtime, further evading detection.
Implications and Recommendations
The emergence of ‘AppleProcessHub’ underscores the evolving threat landscape for macOS users. To mitigate such risks, users and organizations should:
– Exercise Caution: Avoid downloading software from untrusted sources.
– Monitor System Behavior: Be alert to unusual system prompts or unexpected requests for credentials.
– Implement Security Measures: Utilize comprehensive security solutions capable of detecting and responding to advanced threats.
By staying informed and adopting proactive security practices, users can better protect themselves against sophisticated malware like ‘AppleProcessHub.’
