Create sig for network activity from unbacked memory

[kevross33]

For C2 detection of network activity/suspicious activity from unbacked (detected by tracking dynamically allocated) memory to try and detect things like shellcode, beacons etc.

OysterLoader used by Rysida ransomware group 32b0f69e2d046cb835060751fcda28b633cbbd964e6e54dbbc1482fff4d51b57

Xworm

Lumma

[gemini-code-assist]

Summary of Changes

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This pull request introduces a set of new Cuckoo Sandbox signatures designed to bolster command-and-control (C2) detection capabilities. By meticulously tracking dynamically allocated memory regions and monitoring network-related API calls originating from these "unbacked" areas, the changes aim to identify sophisticated fileless malware techniques, such as shellcode execution, C2 beaconing, DNS exfiltration, and bind shell establishment, which often evade traditional signature-based detection.

Highlights

• New Cuckoo Signatures for Unbacked Memory Network Activity: Introduced three new Cuckoo Sandbox signatures to detect suspicious network activity originating from dynamically allocated (unbacked) memory.
• Unbacked Memory Network Connection Detection: Added a signature (UnbackedMemoryNetworkConnection) to identify network API calls (e.g., HttpSendRequest, connect, send) made from unbacked memory regions, indicative of fileless C2 beaconing.
• Unbacked Memory DNS Resolution Detection: Implemented a signature (UnbackedDnsResolution) to detect attempts to resolve domain names (e.g., getaddrinfo, DnsQuery) by code executing within unbacked memory.
• Unbacked Memory Bind Shell Detection: Created a signature (UnbackedBindShell) to flag network socket binding, listening, or accepting connections (e.g., bind, listen, accept) when initiated from unbacked memory, suggesting fileless bind shells or P2P communication.

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[gemini-code-assist]

Code Review

This pull request introduces three new Cuckoo signatures to detect network activity from unbacked memory, which is a valuable technique for identifying fileless malware. The signatures for network connections, DNS resolution, and bind shells are well-defined. The main feedback is regarding significant code duplication across the three new signature classes. Refactoring this into a common base class would greatly improve the maintainability of the code. A specific suggestion has been added to the review.