What is “Worm.Esfury.A”?

The Worm.Esfury.A is considered dangerous by lots of security experts. When this infection is active, you may notice unwanted processes in Task Manager list. In this case, it is adviced to scan your computer with GridinSoft Anti-Malware.

What Worm.Esfury.A virus can do?

• Behavioural detection: Executable code extraction – unpacking
• SetUnhandledExceptionFilter detected (possible anti-debug)
• Yara rule detections observed from a process memory dump/dropped files/CAPE
• Creates RWX memory
• Possible date expiration check, exits too soon after checking local time
• Anomalous file deletion behavior detected (10+)
• Guard pages use detected – possible anti-debugging.
• A process attempted to delay the analysis task.
• Dynamic (imported) function loading detected
• Performs HTTP requests potentially not found in PCAP.
• HTTPS urls from behavior.
• Enumerates running processes
• Expresses interest in specific running processes
• Reads data out of its own binary image
• A process created a hidden window
• Attempts to modify Internet Explorer’s start page
• CAPE extracted potentially suspicious content
• Drops a binary and executes it
• Unconventionial language used in binary resources: Spanish (Chile)
• The binary likely contains encrypted or compressed data.
• Removes Security and Maintenance icon from Start menu, Taskbar and notifications
• Authenticode signature is invalid
• Behavioural detection: Injection (Process Hollowing)
• Executed a process and injected code into it, probably while unpacking
• Behavioural detection: Injection (inter-process)
• Creates or sets a registry key to a long series of bytes, possibly to store a binary or malware config
• Created a process from a suspicious location
• Steals private information from local Internet browsers
• Network activity contains more than one unique useragent.
• Installs itself for autorun at Windows startup
• Overwrites multiple files with zero bytes (hex 00) indicative of a wiper
• Attempts to modify proxy settings
• Operates on local firewall’s policies and settings
• Creates a copy of itself
• Attempts to disable or modify Explorer Folder Options
• Attempts to disable or modify the Run command from the Start menu and the New Task (Run) command from Task Manager
• Attempts to disable System Restore
• Attempts to disable UAC
• The sample wrote data to the system hosts file.
• Attempts to modify or disable Security Center warnings
• Attempts to modify UAC prompt behavior
• Modifies Image File Execution Options, indicative of process injection or persistence
• Anomalous binary characteristics
• Attempts to modify Explorer settings to prevent file extensions from being displayed
• Attempts to modify Explorer settings to prevent hidden files from being displayed
• Attempts to modify user notification settings

How to determine Worm.Esfury.A?

File Info:
name: EE01C35F2A8074AA4245.mlwpath: /opt/CAPEv2/storage/binaries/90cf3aeacfefdd46e77ce0785e519112ef14bbfa33a52f958af9f1da5da97143crc32: 0E0FA919md5: ee01c35f2a8074aa42459fe16c34a411sha1: e5f2b5de87d0ac19ce06ff32acfe2acbf4e71f89sha256: 90cf3aeacfefdd46e77ce0785e519112ef14bbfa33a52f958af9f1da5da97143sha512: 80e71ee8c1f3f5e0f94ee3e8c222306ae2e9c5f001570892a9a5ba8c0c747bda4765a182ee42609072b3bd082216f1ba8ffd5aba4fde871bf847a02cfdf9cbf2ssdeep: 1536:z0HjHkAScR9hXkYQB3k69JusuqdGiA2MvZut+pN5ULmRPYAVPlVDKmQ9x6:zWEcWY9HVX2MvktynULsPemGx6type: PE32 executable (GUI) Intel 80386, for MS Windowstlsh: T14B3502196C2C6931E6CE54B290D78143A8BF583CDAFBA4EB4C900AD0D2750FB5D3616Fsha3_384: 0e03f44f05e89bc24348f8b562ac5dc59c60b62efe3bd382045157b0f61c9e74fe75c9a8842f6d993eaed6d0ec39f7f6ep_bytes: 558becb804100000e873020000a10030timestamp: 2013-06-09 15:24:29
Version Info:
0: [No Data]

Worm.Esfury.A also known as:

How to remove Worm.Esfury.A?

• Download and install GridinSoft Anti-Malware.
• Open GridinSoft Anti-Malware and perform a “Standard scan“.
• “Move to quarantine” all items.
• Open “Tools” tab – Press “Reset Browser Settings“.
• Select proper browser and options – Click “Reset”.
• Restart your computer.