Analysis by: Rhena Inocencio

ALIASES:

Perl/Shellbot (McAfee), Mal/PerlBot-A (Sophos)

 PLATFORM:

Windows, Linux, Unix

 OVERALL RISK RATING:
 DAMAGE POTENTIAL:
 DISTRIBUTION POTENTIAL:
 REPORTED INFECTION:
 INFORMATION EXPOSURE:

  • Threat Type: Backdoor

  • Destructiveness: No

  • Encrypted: No

  • In the wild: Yes

  OVERVIEW

Infection Channel: Downloaded from the Internet

This backdoor executes commands from a remote malicious user, effectively compromising the affected system.

  TECHNICAL DETAILS

File Size: 23,642 bytes
File Type: Script
Memory Resident: Yes
Initial Samples Received Date: 03 Oct 2014
Payload: Compromises system security, Connects to URLs/IPs

Arrival Details

This backdoor may be downloaded from the following remote site(s):

  • http://{BLOCKED}x.com/shock/cgi

Backdoor Routine

This backdoor connects to any of the following IRC server(s):

  • irc.{BLOCKED}k.tk:6667
  • {BLOCKED}.{BLOCKED}.50.237:6969

It joins any of the following IRC channel(s):

  • #xrt

It executes the following commands from a remote malicious user:

  • system - Get OS name and version, system uptime, current process name, user ID, group ID and current directory
  • portscan - Scan an IP address for the following ports: 15, 19, 98, 20, 21, 22, 23, 25, 37, 39, 42, 43, 49, 53, 63, 69, 79, 80, 101, 106, 107, 109, 110, 111, 113, 115, 117, 119, 135, 137, 139, 143, 174, 194, 389, 389, 427, 443, 444, 445, 464, 488, 512, 513, 514, 520, 540, 546, 548, 565, 609, 631, 636, 694, 749, 750, 767, 774, 783, 808, 902, 988, 993, 994, 995, 1005, 1025, 1033, 1066, 1079, 1080, 1109, 1433, 1434, 1512, 2049, 2105, 2432, 2583, 3128, 3306, 4321, 5000, 5222, 5223, 5269, 5555, 6660, 6661, 6662, 6663, 6665, 6666, 6667, 6668, 6669, 7000, 7001, 7741, 8000, 8018, 8080, 8200, 10000, 19150, 27374, 31310, 33133, 33733, 55555
  • tcpflood - Perform TCP flooding
  • httpflood - Perform HTTP flooding
  • sqlflood - Perform SQL flooding
  • udpflood - Perform UDP flooding
  • logcleaner - Deletes all files in the following directories:
    • /var/log/lastlog
    • /var/log/wtmp
    • /etc/wtmp
    • /var/run/utmp
    • /etc/utmp
    • /var/log
    • /var/logs
    • /var/adm
    • /var/apache/log
    • /var/apache/logs
    • /usr/local/apache/log
    • /usr/local/apache/logs
    • /root/.bash_history
    • /root/.ksh_history
  • rootable - Enumerates possible root exploits in the infected system
  • socks5 - Set up SOCKSv5 protocol
  • sendmail - Send an email to a target

  SOLUTION

Minimum Scan Engine: 9.700
FIRST VSAPI PATTERN FILE: 11.188.03
FIRST VSAPI PATTERN DATE: 03 Oct 2014

Scan your computer with your Trend Micro product to delete files detected as PERL_SHELLBOT.XB. If the detected files have already been cleaned, deleted, or quarantined by your Trend Micro product, no further step is required. You may opt to simply delete the quarantined files. Please check this Knowledge Base page for more information.


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