Concrete signature match: DDoS for Linux platform, family Lightaidra
This is a concrete detection of DDoS:Linux/Lightaidra, a sophisticated Linux-based DDoS botnet client. It enables attackers to perform network scanning, brute-force attacks, file transfers (FTP), and launch various denial-of-service attacks, contributing to a botnet infrastructure. The presence of specific IRC, scanning, and flooding-related strings confirms its malicious intent.
Relevant strings associated with this threat: - !#HSTR:StringCodeForMshta.A!pli (PEHSTR_EXT) - !#HSTR:StringCodeForHooking.C!pli (PEHSTR_EXT) - !#HSTR:StringCodeForHooking.D!pli (PEHSTR_EXT) - !#HSTR:StringCodeForHooking.L!pli (PEHSTR_EXT) - !#HSTR:StringCodeForHooking.O!pli (PEHSTR_EXT) - !#HSTR:StringCodeForRegsvr32.A!pli (PEHSTR_EXT) - !#HSTR:StringCodeForRundll32.A!pli (PEHSTR_EXT) - rundll32 (PEHSTR_EXT) - !#HSTR:StringCodeForBITSJobs.A!pli (PEHSTR_EXT) - !#HSTR:StringCodeForPowerShell.G!pli (PEHSTR_EXT) - !#HSTR:StringCodeForScheduledTask.A!pli (PEHSTR_EXT) - !#HSTR:StringCodeForDataEncoding.D!pli (PEHSTR_EXT) - !#HSTR:StringCodeForHooking.J!pli (PEHSTR_EXT) - !#HSTR:StringCodeForHooking.K!pli (PEHSTR_EXT) - !#HSTR:StringCodeForRemoteFileCopy.B!pli (PEHSTR_EXT) - !#HSTR:ExecutionGuardrails (PEHSTR_EXT) - !#HSTR:StringCodeForFileDeletion.A!pli (PEHSTR_EXT) - !#HSTR:StringCodeForHooking.M!pli (PEHSTR_EXT) - !#HSTR:StringCodeForNetshHelperDLL.A!pli (PEHSTR_EXT) - !#HSTR:StringCodeForRemoteServices.A!pli (PEHSTR_EXT)
rule DDoS_Linux_Lightaidra_2147717463_0
{
meta:
author = "threatcheck.sh"
detection_name = "DDoS:Linux/Lightaidra"
threat_id = "2147717463"
type = "DDoS"
platform = "Linux: Linux platform"
family = "Lightaidra"
severity = "Critical"
signature_type = "SIGNATURE_TYPE_ELFHSTR_EXT"
threshold = "11"
strings_accuracy = "High"
strings:
$x_1_1 = "irc_" ascii //weight: 1
$x_1_2 = "scan" ascii //weight: 1
$x_1_3 = "flood" ascii //weight: 1
$x_1_4 = "attack" ascii //weight: 1
$x_1_5 = "fin.ack" ascii //weight: 1
$x_1_6 = "password" ascii //weight: 1
$x_1_7 = "root" ascii //weight: 1
$x_1_8 = "shell" ascii //weight: 1
$x_1_9 = "ftpget" ascii //weight: 1
$x_1_10 = "admin1234" ascii //weight: 1
$x_1_11 = "XA1bac0MX" ascii //weight: 1
$x_1_12 = "dreambox" ascii //weight: 1
condition:
(filesize < 20MB) and
(11 of ($x*))
}5739b534112d327669d19a06fa1ea6fba6bf5510f283dfd2ac561f4edf6b986328a8fd63053552448f5571b1c08065e8acd21985610a3135e71a524a3e68d0c0fd8f404aeb0b25dccb13a9b97b35c95ca8cb45a126db0014c81fc1992f02a408f72745502b04fa6c2de5c49534846085cc3be574f364b7884af1e910198d63c5a093743fdd8267704bc8dbe330f458da98c8c1a52b72ddee473c34efb0306430Immediately isolate the infected Linux system from the network. Conduct a thorough forensic analysis, remove the malware, patch all system vulnerabilities, and change any compromised credentials. Implement robust network segmentation, intrusion detection/prevention systems, and ensure regular security audits to prevent future infections.