MAR-10400779-2.v1 – Zimbra 2
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Download the STIX version of this report: MAR-10400779.r2.v1.WHITE_stix, 1.3 MB
CISA received a Java Server Pages (JSP) webshell file for analysis. The JSP file allows an attacker to execute shell commands and read the output of the commands.
Submitted Files (1)
No matches found.
This file is a JSP webshell that allows an attacker to execute shell commands and read the output of the commands. When executed, it prompts the attacker to enter the shell command to be executed. It checks whether the command supplied by the attacker through the "cmd" parameters contain null values (blank). If it contains null values, the command input stream will be displayed in a JSP page in the format below:
If the system platform is Windows, it executes the user-provided commands via "cmd.exe /c <commands>". Otherwise, it will execute the user-provided commands in the shell. The command output will be displayed in a JSP page.
Figure 1 - The contents of the JSP file. It contains a form with input fields that prompts the attacker to enter the command in the input box to execute.
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".
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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.
Initial Version: September 27, 2022