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This document is marked TLP:WHITE--Disclosure is not limited. Sources may use TLP:WHITE when information carries minimal or no foreseeable risk of misuse, in accordance with applicable rules and procedures for public release. Subject to standard copyright rules, TLP:WHITE information may be distributed without restriction. For more information on the Traffic Light Protocol (TLP), see http://www.cisa.gov/tlp.
CISA received one unique file for analysis. This file is a malicious 32-bit Windows Portable Executable (PE). During runtime, this malware attempts to overwrite the victim user's files with null bytes. The malware also attempts to overwrite the Master Boot Record of attached drives with null bytes, thereby corrupting them and rendering it impossible for the victim to access the victim's stored data.
For a downloadable copy of IOCs, see: MAR-10376640-2.v1.stix.
Submitted Files (1)
No matches found.
This file is a 32 bit Windows PE that has been identified as a variant of the malware family known as Caddy Wiper. Static analysis of this application indicates its primary purpose is to destroy victim user data. First the malware attempts to enumerate all files in the directory "C:\Users". The malware will then attempt to recursively overwrite files that it can access in this directory with null bytes, effectively "zeroing" the files out.
Figure 1. - This screenshot illustrates the main structure of the malware. As illustrated, the malware's main purpose is to recursively overwrite victim user's files and physical drives with null bytes.
Figure 2. - Structure that malware uses to build null buffer. This buffer is utilized to overwrite the victim user's target files.
Figure 3. - Malware trying to zero out \\.\PHYSICALDRIVE7
Figure 4. - Malware trying to zero out \\.\PHYSICALDRIVE4
Figure 5. - Malware trying to zero out \\.\PHYSICALDRIVE3
Figure 6. - Malware attempting to zero out first 1920 bytes of a physical drive attached to the target system.
CISA recommends that users and administrators consider using the following best practices to strengthen the security posture of their organization's systems. Any configuration changes should be reviewed by system owners and administrators prior to implementation to avoid unwanted impacts.
Additional information on malware incident prevention and handling can be found in National Institute of Standards and Technology (NIST) Special Publication 800-83, "Guide to Malware Incident Prevention & Handling for Desktops and Laptops".
CISA continuously strives to improve its products and services. You can help by answering a very short series of questions about this product at the following URL: https://us-cert.cisa.gov/forms/feedback/
What is a MIFR? A Malware Initial Findings Report (MIFR) is intended to provide organizations with malware analysis in a timely manner. In most instances this report will provide initial indicators for computer and network defense. To request additional analysis, please contact CISA and provide information regarding the level of desired analysis.
What is a MAR? A Malware Analysis Report (MAR) is intended to provide organizations with more detailed malware analysis acquired via manual reverse engineering. To request additional analysis, please contact CISA and provide information regarding the level of desired analysis.
Can I edit this document? This document is not to be edited in any way by recipients. All comments or questions related to this document should be directed to the CISA at 1-888-282-0870 or CISA Service Desk.
Can I submit malware to CISA? Malware samples can be submitted via three methods:
CISA encourages you to report any suspicious activity, including cybersecurity incidents, possible malicious code, software vulnerabilities, and phishing-related scams. Reporting forms can be found on CISA's homepage at www.cisa.gov.
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