MalwareBazaar Database

You are currently viewing the MalwareBazaar entry for SHA256 bb885bf6e5cf58dfa576c8bdd006f80c779ae33a446fc152652eac71ed8db27d. 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


Threat unknown


Vendor detections: 5


Intelligence 5 IOCs YARA 1 File information Comments
Download sample Add tag Delete this sample Report a False Positive

SHA256 hash: bb885bf6e5cf58dfa576c8bdd006f80c779ae33a446fc152652eac71ed8db27d
SHA3-384 hash: 01438bd45f858e903bb83c96caae024ba37c1293801014117c98eb44bf459821120246b9c0a09a98eea02db741dba7c8
SHA1 hash: ca5c0bd1177893eeb4af6ec9bd35704f1a654558
MD5 hash: 2fe76ffad31bc6945809f5a734b86da9
humanhash: diet-mars-mirror-echo
File name:kworkerd-writeback
Download: download sample
File size:110'728 bytes
First seen:2026-06-25 18:58:26 UTC
Last seen:Never
File type: elf
MIME type:application/x-sharedlib
ssdeep 3072:cWyeZBk9QDxaSRcNrhMC/S265494u+qgwM4h:PZBkox3a7MCs40g
TLSH T183B31252E1F9DC1BEF6A84B209478DDD629C875F3F4EA62120078D90951199FBB9C8C3
Magika elf
Reporter abuse_ch
Tags:elf UPX
File size (compressed) :110'728 bytes
File size (de-compressed) :329'172 bytes
Format:linux/ppc32
Unpacked file: 5e78e6c39fb638de7536bbf6ceb21ebb6ae852f190447edb751c3a422544e780

Intelligence

File Origin
# of uploads :
1
# of downloads :
52
Origin country :
DE DE
Vendor Threat Intelligence
No detections
Result
Verdict:
Malware
Maliciousness:

Behaviour
Creating a file in the %temp% directory
Connection attempt
Opens a port
Changes access rights for a written file
Receives data from a server
Changes the time when the file was created, accessed, or modified
DNS request
Runs as daemon
Sets a written file as executable
Manages services
Collects information on the CPU
Creating a file
Sends data to a server
Launching a process
Creates or modifies files in /cron to set up autorun
Substitutes an application name
Kills critical processes
Deleting of the original file
Creates or modifies files in /init.d to set up autorun
Verdict:
Unknown
Threat level:
  0/10
Confidence:
100%
Tags:
packed upx
Link:
https://www.filescan.io/uploads/6a3d7a579569cb5d28bdc5ea/reports/9db13b35-a931-485f-bca2-12446525a215/overview
Status:
terminated
Link:
https://sandbox.kunai.rocks/analysis/9baaa62f-6867-4efb-8ffd-ba8475424bc6
Behavior Graph:
Download SVG
%3 guuid=8970df34-1f00-0000-432f-fba940140000 pid=5184 /usr/bin/sudo guuid=2a930e37-1f00-0000-432f-fba941140000 pid=5185 /tmp/sample.bin guuid=8970df34-1f00-0000-432f-fba940140000 pid=5184->guuid=2a930e37-1f00-0000-432f-fba941140000 pid=5185 execve
Verdict:
Unknown
Link:
https://analyze.intezer.com/analyses/9ff6d248-c74a-484a-a128-7f7832cbb1d7
Result
Threat name:
Xmrig
Create hunting rule
Detection:
malicious
Classification:
troj.spyw.evad.mine
Score:
96 / 100
Link:
https://www.joesandbox.com/analysis/1933928
Signature
Antivirus detection for dropped file
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
Executes the "nc" (netcat) command used to establish arbitrary TCP or UDP connections and listens
Found strings related to Crypto-Mining
Opens /sys/class/net/* files useful for querying network interface information
Performs DNS TXT record lookups
Sample deletes itself
Sample tries to persist itself using cron
Searches for CPU information (likely indicative of DDoS capability)
Yara detected Xmrig cryptocurrency miner
Behaviour
Behavior Graph:
Download SVG
behaviorgraph top1 dnsIp2 2 Behavior Graph ID: 1933928 Sample: kworkerd-writeback.elf Startdate: 25/06/2026 Architecture: LINUX Score: 96 84 api.robotmarkethub.com 2->84 86 91.239.211.89, 37744, 39226, 39228 HOSTKEY-ASNL Germany 2->86 88 99 other IPs or domains 2->88 98 Antivirus detection for dropped file 2->98 100 Yara detected Xmrig cryptocurrency miner 2->100 12 systemd sh 2->12         started        14 kworkerd-writeback.elf 2->14         started        17 systemd snapd-env-generator 2->17         started        19 systemd snapd-env-generator 2->19         started        signatures3 102 Performs DNS TXT record lookups 84->102 process4 signatures5 21 sh sh 12->21         started        24 sh wget 12->24         started        26 sh rm 12->26         started        118 Found strings related to Crypto-Mining 14->118 28 kworkerd-writeback.elf 14->28         started        process6 file7 80 /dev/shm/.exectest.5573, POSIX 21->80 dropped 30 sh .d 21->30         started        32 sh wget 21->32         started        36 sh 21->36         started        40 28 other processes 21->40 82 /tmp/..redis-sentinel, POSIX 24->82 dropped 38 kworkerd-writeback.elf 28->38         started        process8 file9 42 .d 30->42         started        74 /dev/shm/.d, ELF 32->74 dropped 90 Drops invisible ELF files 32->90 44 sh grep 36->44         started        47 kworkerd-writeback.elf sh 38->47         started        49 kworkerd-writeback.elf sh 38->49         started        92 Searches for CPU information (likely indicative of DDoS capability) 40->92 94 Sample deletes itself 40->94 96 Executes the "nc" (netcat) command used to establish arbitrary TCP or UDP connections and listens 40->96 signatures10 process11 signatures12 51 .d 42->51         started        116 Searches for CPU information (likely indicative of DDoS capability) 44->116 55 sh systemctl 47->55         started        57 sh systemctl 49->57         started        process13 file14 76 /var/spool/cron/crontabs/root, ASCII 51->76 dropped 104 Opens /sys/class/net/* files useful for querying network interface information 51->104 106 Sample deletes itself 51->106 108 Sample tries to persist itself using cron 51->108 59 .d sh 51->59         started        62 .d sh 51->62         started        64 .d 51->64         started        66 199 other processes 51->66 signatures15 process16 signatures17 114 Executes itself again with its parent PID as an argument (indicative of hampering debugging) 59->114 68 sh crontab 59->68         started        72 sh crontab 62->72         started        process18 file19 78 /var/spool/cron/crontabs/tmp.n5Jsrg, ASCII 68->78 dropped 110 Sample tries to persist itself using cron 68->110 112 Executes the "crontab" command typically for achieving persistence 68->112 signatures20
Score:
100%
Verdict:
Malware
File Type:
ELF
Link:
https://malprob.io/report/bb885bf6e5cf58dfa576c8bdd006f80c779ae33a446fc152652eac71ed8db27d
Detection:
n/a
Link:
https://mwdb.cert.pl/sample/bb885bf6e5cf58dfa576c8bdd006f80c779ae33a446fc152652eac71ed8db27d/
Gathering data
Detection(s):
Suspicious file
Link:
https://check.spamhaus.org/check/?searchterm=xoefx5xfz5mn7jlwzc65abxybr3zvyz2irx4cutff2whd3mnwj6q._file
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/bb885bf6e5cf58dfa576c8bdd006f80c779ae33a446fc152652eac71ed8db27d

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:CP_Script_Inject_Detector
Create hunting rule
Author:DiegoAnalytics
Description:Detects attempts to inject code into another process across PE, ELF, Mach-O binaries

File information

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

Web download

elf bb885bf6e5cf58dfa576c8bdd006f80c779ae33a446fc152652eac71ed8db27d

(this sample)

elf 5e78e6c39fb638de7536bbf6ceb21ebb6ae852f190447edb751c3a422544e780

  
URLhaus
https://urlhaus.abuse.ch/url/3868024/
  
Delivery method
Distributed via web download
  
Dropping
SHA256 5e78e6c39fb638de7536bbf6ceb21ebb6ae852f190447edb751c3a422544e780
  
Dropping
MD5 0ed8a6fa5fe633a3426db02b1bd67230

Comments