MalwareBazaar Database

You are currently viewing the MalwareBazaar entry for SHA256 f13cb360768363d3424e2192c7805b8c8015eb8706dbbbcdead6aed8cf390109. While MalwareBazaar tries to identify whether the sample provided is malicious or not, there is no guarantee that a sample in MalwareBazaar is malicious.

Database Entry


Mirai


Vendor detections: 5


Intelligence 5 IOCs YARA 5 File information Comments
Download sample Add tag Delete this sample Report a False Positive

SHA256 hash: f13cb360768363d3424e2192c7805b8c8015eb8706dbbbcdead6aed8cf390109
SHA3-384 hash: ab1350ae1c085c79ed2ea1284eae1a27b1ebe53ac05cab97118dc7264577fdec293f453b00691180e716637ad22e3762
SHA1 hash: 4c7b271348d729f72f776d9b6284d1b32f01b17e
MD5 hash: 531dca50d5fd9c6f6ba3e5d7aaf42a2c
humanhash: hawaii-dakota-gee-purple
File name:kworkerd-rcu
Download: download sample
Signature Mirai
Create hunting rule
File size:451'156 bytes
First seen:2026-07-14 02:17:04 UTC
Last seen:Never
File type: elf
MIME type:application/x-executable
ssdeep 12288:CcGbDx0EgHJ25HHUUZvRF14Tfr20lbsaJbah:5CD6HJmUU5HaTfr7sob
TLSH T1D8A4231594079D8BFC19FCF90D7B01351E887E0F29D7A2A48024FD7E36BE9A64CD2A58
Magika elf
Reporter abuse_ch
Tags:elf mirai

Intelligence

File Origin
# of uploads :
1
# of downloads :
93
Origin country :
DE DE
Vendor Threat Intelligence
No detections
Result
Verdict:
Malware
Maliciousness:

Behaviour
Creating a file
Sets a written file as executable
Creating a file in the %temp% directory
Runs as daemon
Changes access rights for a written file
Manages services
Kills processes
Deleting a recently created file
Creating a process from a recently created file
Changes the time when the file was created, accessed, or modified
Opens a port
Launching a process
Connection attempt
Substitutes an application name
Creates or modifies files in /cron to set up autorun
Creates or modifies files to set up autorun
Creates or modifies files in /init.d to set up autorun
Verdict:
Unknown
Threat level:
  0/10
Confidence:
100%
Tags:
gcc
Link:
https://www.filescan.io/uploads/6a559c3a9af89c89f13fd435/reports/0b3484f0-f3a0-446b-832b-e9e1187a7580/overview
Status:
terminated
Link:
https://sandbox.kunai.rocks/analysis/28770da8-b8c2-4d8f-a7c5-c4052ab62f68
Behavior Graph:
Download SVG
%3 guuid=dc490c42-1900-0000-5b5f-c2362b140000 pid=5163 /usr/bin/sudo guuid=a5326d44-1900-0000-5b5f-c2362c140000 pid=5164 /tmp/sample.bin guuid=dc490c42-1900-0000-5b5f-c2362b140000 pid=5163->guuid=a5326d44-1900-0000-5b5f-c2362c140000 pid=5164 execve
Verdict:
Unknown
Link:
https://analyze.intezer.com/analyses/50cebe72-45f8-4a78-ad60-086eeb72fdc3
Result
Threat name:
Mirai, Xmrig
Create hunting rule
Detection:
malicious
Classification:
spre.troj.spyw.evad.mine
Score:
100 / 100
Link:
https://www.joesandbox.com/analysis/1941916
Signature
Antivirus detection for dropped file
Drops files in suspicious directories
Drops invisible ELF files
Executes itself again with its parent PID as an argument (indicative of hampering debugging)
Executes the "crontab" command typically for achieving persistence
Found strings related to Crypto-Mining
Malicious sample detected (through community Yara rule)
Opens /sys/class/net/* files useful for querying network interface information
Sample deletes itself
Sample tries to persist itself using /etc/profile
Sample tries to persist itself using cron
Sample tries to set files in /etc globally writable
Yara detected Mirai
Yara detected Xmrig cryptocurrency miner
Behaviour
Behavior Graph:
Download SVG
behaviorgraph top1 dnsIp2 2 Behavior Graph ID: 1941916 Sample: kworkerd-rcu.elf Startdate: 14/07/2026 Architecture: LINUX Score: 100 82 91.92.40.118, 443, 44472, 44474 TODYL-CLOUD-TodylIncUS Bulgaria 2->82 84 109.202.202.202, 80 INIT7CH Switzerland 2->84 86 3 other IPs or domains 2->86 90 Malicious sample detected (through community Yara rule) 2->90 92 Antivirus detection for dropped file 2->92 94 Yara detected Mirai 2->94 96 Yara detected Xmrig cryptocurrency miner 2->96 11 kworkerd-rcu.elf 2->11         started        15 systemd sh 2->15         started        17 systemd snapd-env-generator 2->17         started        19 3 other processes 2->19 signatures3 process4 file5 80 /tmp/.6238, ELF 11->80 dropped 112 Drops invisible ELF files 11->112 114 Sample deletes itself 11->114 21 kworkerd-rcu.elf .6238 11->21         started        24 sh sh 15->24         started        26 sh wget 15->26         started        29 sh rm 15->29         started        signatures6 process7 file8 98 Found strings related to Crypto-Mining 21->98 31 .6238 21->31         started        33 sh wget 24->33         started        37 sh .k 24->37         started        39 sh chmod 24->39         started        76 /tmp/..redis-sentinel, POSIX 26->76 dropped signatures9 process10 file11 41 .6238 31->41         started        70 /tmp/.k, ELF 33->70 dropped 88 Drops invisible ELF files 33->88 45 .k 37->45         started        signatures12 process13 file14 72 /etc/profile.d/red...aof-rewrite-onwv.sh, ASCII 41->72 dropped 74 /etc/init.d/redis-...ck aof-rewrite-8ewc, POSIX 41->74 dropped 100 Sample tries to set files in /etc globally writable 41->100 102 Opens /sys/class/net/* files useful for querying network interface information 41->102 104 Sample tries to persist itself using /etc/profile 41->104 106 Drops files in suspicious directories 41->106 47 .6238 sh 41->47         started        50 .6238 sh 41->50         started        52 .6238 sh 41->52         started        56 2 other processes 41->56 54 .k 45->54         started        signatures15 process16 signatures17 116 Executes itself again with its parent PID as an argument (indicative of hampering debugging) 47->116 58 sh crontab 47->58         started        62 sh crontab 50->62         started        64 sh systemctl 52->64         started        66 sh systemctl 56->66         started        68 sh update-rc.d 56->68         started        process18 file19 78 /var/spool/cron/crontabs/tmp.vgJdAO, ASCII 58->78 dropped 108 Sample tries to persist itself using cron 58->108 110 Executes the "crontab" command typically for achieving persistence 58->110 signatures20
Score:
100%
Verdict:
Malware
File Type:
ELF
Link:
https://malprob.io/report/f13cb360768363d3424e2192c7805b8c8015eb8706dbbbcdead6aed8cf390109
Detection:
n/a
Link:
https://mwdb.cert.pl/sample/f13cb360768363d3424e2192c7805b8c8015eb8706dbbbcdead6aed8cf390109/
Detection(s):
Suspicious file
Link:
https://check.spamhaus.org/check/?searchterm=6e6lgydwqnr5gqsoegjmpac3rsabl24ha3n3xtpk22xnrtzzaeeq._file
Result
Malware family:
n/a
Score:
  7/10
Tags:
n/a
Link:
https://tria.ge/reports/260714-cqzwzscv9k/
Behaviour
Writes file to tmp directory
Executes dropped EXE
Please note that we are no longer able to provide a coverage score for Virus Total.
Threat name:
Legit
Score:
0.00
Link:
https://yomi.yoroi.company/submissions/f13cb360768363d3424e2192c7805b8c8015eb8706dbbbcdead6aed8cf390109

YARA Signatures

MalwareBazaar uses YARA rules from several public and non-public repositories, such as YARAhub and Malpedia. Those are being matched against malware samples uploaded to MalwareBazaar as well as against any suspicious process dumps they may create. Please note that only results from TLP:CLEAR rules are being displayed.

Rule name:enterpriseapps2
Create hunting rule
Author:Tim Brown @timb_machine
Description:Enterprise apps
Rule name:enterpriseunix2
Create hunting rule
Author:Tim Brown @timb_machine
Description:Enterprise UNIX
Rule name:linux_generic_ipv6_catcher
Create hunting rule
Author:@_lubiedo
Description:ELF samples using IPv6 addresses
Rule name:TH_Generic_MassHunt_Linux_Malware_2026_CYFARE
Create hunting rule
Author:CYFARE
Description:Generic Linux malware mass-hunt rule - 2026
Reference:https://cyfare.net/
Rule name:unixredflags3
Create hunting rule
Author:Tim Brown @timb_machine
Description:Hunts for UNIX red flags

File information

The table below shows additional information about this malware sample such as delivery method and external references.

Web download

Mirai

elf f13cb360768363d3424e2192c7805b8c8015eb8706dbbbcdead6aed8cf390109

(this sample)

  
URLhaus
https://urlhaus.abuse.ch/url/3883717/
  
Delivery method
Distributed via web download

Comments