H1N1 is a malware variant that has evolved to include information-stealing functionality. It affects the following operating systems: ['Windows']. H1N1 kills and disables services for Windows Firewall and Windows Security Center, and Windows Defender. H1N1 uses multiple techniques to obfuscate strings, including XOR. H1N1 has functionality to copy itself to removable media and network shares. H1N1 contains a command to download and execute a file from a remotely hosted URL using WinINet HTTP requests.
H1N1 Malware Capabilities
H1N1 may attempt to evade detection and removal by deleting or removing built-in operating system data, disabling security tools, and/or encoding command and control traffic. The malware may also spread to other systems via removable media, using Autorun features to execute malware on the target system.
- H1N1 is a malware that may disable or modify system firewalls in order to bypass controls limiting network usage. It may also encode data to make the content of command and control traffic more difficult to detect. Additionally, H1N1 may acquire credentials from web browsers by reading files specific to the target browser.
- H1N1 is a virus that may use symmetric encryption to conceal command and control traffic, delete or remove built-in operating system data, and bypass UAC mechanisms to elevate process privileges on a system. This may deny access to available backups and recovery options.
- The malware H1N1 may attempt to evade detection by security tools, make itself difficult to discover or analyze, and/or move onto other systems by copying itself to removable media. This behavior could allow H1N1 to spread to disconnected or air-gapped networks.
- The H1N1 malware may transfer tools or other files from an external system into a compromised environment. This may be done through the command and control channel or through alternate protocols such as FTP. Once present, the malware may transfer/spread tools between victim devices within a compromised environment. Additionally, the H1N1 malware may abuse the Windows command shell for execution. This allows the malware to control almost any aspect of a system, with various permission levels required for different subsets of commands. The command prompt can be invoked remotely via services such as SSH.
Ways to Mitigate H1N1 Malware Attacks
- The best way to mitigate H1N1 malware attacks is to monitor processes and command-line arguments, analyze network data, and identify web browser files that contain credentials. By doing so, you can detect suspicious behavior and take appropriate action.
- The H1N1 malware can be mitigated by using symmetric encryption to decode network traffic and detect malware communications signatures. Additionally, process monitoring can be used to monitor the execution and command line parameters of binaries involved in inhibiting system recovery. Finally, UAC bypasses can be detected by monitoring process API calls and loaded DLLs.
- The H1N1 malware can be detected and mitigated by monitoring processes, command line arguments, and registry edits for modifications to security tools and services. Additionally, file access on removable media can be monitored for H1N1 malware activity.
- Usage of the Windows command shell may be common on administrator, developer, or power user systems depending on job function. If scripting is restricted for normal users, then any attempt to enable scripts running on a system would be considered suspicious. Finally, processes that write or overwrite many files to a network shared directory may be suspicious.