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Summary

Description

CISA received two Common Gateway Interface (CGI) scripts for analysis. The two CGI scripts are Pulse Secure system files that were modified by a malicious actor. The files contain a malicious modification which allows the attacker to maintain remote command and control (C2) access to a target system. This analysis is derived from malicious files found on Pulse Connect Secure devices.

For a downloadable copy of indicators of compromise, see: MAR-10336935-2.v1.stix.

Submitted Files (2)

c287cd9e3c37f5869dbce168a89a78836a61791a72b36d048c086576b9af2769 (licenseserverproto.cgi)

d27730060be3099846a673cfee890da05dc9f7b34d987c65f4299980b6865822 (licenseserverproto.cgi)

Findings

d27730060be3099846a673cfee890da05dc9f7b34d987c65f4299980b6865822

Tags

backdoortrojan

Details
Name licenseserverproto.cgi
Size 3377 bytes
Type Perl script text executable
MD5 ae76be46d7e1ca140cf4d30d5a60d407
SHA1 0dc2f82d9392b9b0646fa65523e2da712a401e99
SHA256 d27730060be3099846a673cfee890da05dc9f7b34d987c65f4299980b6865822
SHA512 29f46f49a3d700d1f8b88df8d20eed3a834fccaf0057754d465cd27017332dd9ef2efc47c49315091d55d1c0afdbb14b433a4a3458372e74ae24f0524fccc664
ssdeep 48:ErLYmeAJAZo6HMeQT808inRbxhcQjQkBQVeWo7BuswT4o7oo7vpBBBQWBZ7zSH74:EfYkJAZnqpxhcOQVHo0v/wO27YJ
Entropy 5.316307
Antivirus

No matches found.

YARA Rules

No matches found.

ssdeep Matches
91 ade49335dd276f96fe3ba89de5eb02ea380901b5ef60ff6311235b6318c57f66
97 c287cd9e3c37f5869dbce168a89a78836a61791a72b36d048c086576b9af2769
Description

This is a CGI script that was maliciously modified (Figure 1) from a Pulse Secure system file. The malicious form accepts a command of no more than 45 characters in length. The script executes the provided command on the compromised system using the system function.

Screenshots

Figure 1 - Screenshot of the dependencies and the malicious main() function patched into the Pulse Secure file.