AvosLocker

MITRE ATT&CK: S1053 View on attack.mitre.org

Aliases: Avos, AvosLocker

First seen
2021-06-01 00:00:00
Malware type
ransomware
Family
Malware family
Operating systems
linux, windows
Related IoCs
71 (71 malicious)
Last IoC activity
2026-08-28 02:50:47
Profile updated
2026-07-07 13:05:15

Targeted industries: financial-services government-and-public-sector manufacturing

Targeted regions: country_code:us country_code:be country_code:ca country_code:cn country_code:de country_code:sa country_code:es country_code:sy country_code:tw country_code:tr country_code:ae country_code:gb

Context

AvosLocker is ransomware written in C++ that has been offered via the Ransomware-as-a-Service (RaaS) model. It was first observed in June 2021 and has been used against financial services, critical manufacturing, government facilities, and other critical infrastructure sectors in the United States. As of March 2022, AvosLocker had also been used against organizations in Belgium, Canada, China, Germany, Saudi Arabia, Spain, Syria, Taiwan, Turkey, the United Arab Emirates, and the United Kingdom.

Recent IoC activity

71 malicious indicators in Maltiverse are attributed to AvosLocker (S1053). The 20 most recently updated:

TypeIndicatorUpdatedSources
file sample 2026-03-16_9f8b04941e1dc337c2074aa0137f43e1_amadey_avoslocker_cobalt-strike_e... 2026-08-28 1
file sample 2026-08-23_118dd1d9fcc3e6de933d51e8366e363d_amadey_avoslocker_cobalt-strike_e... 2026-08-24 1
file sample test.exe 2026-08-21 2
file sample 718810b8eeb682fc70df602d952c0c83e028c5a5bfa44c506756980caf2edebb.zip 2026-08-17 1
file sample ffd933ad53f22a0f10cceb4986087258f72dffdd36999b7014c6b37c157ee45f.7z 2026-07-18 1
file sample 2026-03-15_6047c70ac2a63763cb5d714597332b22_amadey_avoslocker_cobalt-strike_e... 2026-07-14 1
file sample 2026-03-12_930396ca316e4d07121ca04601aafc0e_amadey_avoslocker_cobalt-strike_e... 2026-07-13 1
file sample 2026-03-14_b62cedc9295c5294d4e0728eca12f19a_amadey_avoslocker_cobalt-strike_e... 2026-06-30 1
file sample 2026-03-16_762c4eca71a0036cbf97775f0a925fe3_amadey_avoslocker_cobalt-strike_e... 2026-06-22 1
file sample 2026-03-11_ac3d64cdda1df38f04478f6307ae15f1_amadey_avoslocker_cobalt-strike_e... 2026-06-19 1
file sample bff12a83b1fc2e0ad0000ad9b68abc8eada559bb1094caaf5b9f52887df23705.exe 2026-06-18 4
file sample 2026-03-12_12589b240a3e84806959bfded9876c21_amadey_avoslocker_cobalt-strike_e... 2026-06-15 1
file sample 0cd7b6ea8857ce827180342a1c955e79c3336a6cf2000244e5cfd4279c5fc1b6 2026-04-12 2
file sample e9a7b43acdddc3d2101995a2e2072381449054a7d8d381e6dc6ed64153c9c96a.elf 2026-04-04 2
file sample d7112a1e1c68c366c05bbede9dbe782bb434231f84e5a72a724cc8345d8d9d13 2026-04-04 1
file sample 84d94c032543e8797a514323b0b8fd8bd69b4183f17351628b13d1464093af2d.bin 2026-03-26 1
file sample 2026-03-20_24c2115b34a51b5cff163d9a874bb5bc_amadey_avoslocker_cobalt-strike_e... 2026-03-20 1
file sample 2026-03-18_f2a92089091b443f2a236cc36d0a0e29_amadey_avoslocker_cobalt-strike_e... 2026-03-18 1
file sample 2026-03-18_9cbca3c0039f2b4a2f61649f05c836b0_amadey_avoslocker_cobalt-strike_e... 2026-03-18 1
file sample 2026-03-18_805db7a466f17dc7982a3cf54297e230_amadey_avoslocker_cobalt-strike_e... 2026-03-18 1

Detection coverage

  • 6 YARA rules
  • 223 Sigma rules

Malware & tools used

  • Native API (attack-pattern)
  • Safe Mode Boot (attack-pattern)
  • Data Encrypted for Impact (attack-pattern)
  • Registry Run Keys / Startup Folder (attack-pattern)
  • Deobfuscate/Decode Files or Information (attack-pattern)
  • Dynamic API Resolution (attack-pattern)
  • File and Directory Discovery (attack-pattern)
  • Masquerade File Type (attack-pattern)
  • Hidden Window (attack-pattern)
  • Service Stop (attack-pattern)
  • Network Share Discovery (attack-pattern)
  • Obfuscated Files or Information (attack-pattern)
  • System Time Discovery (attack-pattern)
  • Process Discovery (attack-pattern)
  • System Shutdown/Reboot (attack-pattern)

Used by threat actors

  • C0018 (campaign)

Detection rules

  • MALPEDIA_Win_Avos_Locker_Auto (yara-rule)
  • TRELLIX_ARC_Ransom_Avoslocker (yara-rule)
  • ARKBIRD_SOLG_RAN_Avoslocker_July_2021_1 (yara-rule)
  • DITEKSHEN_MALWARE_Win_Avoslocker (yara-rule)
  • SEKOIA_Ransomware_Win_Avoslocker (yara-rule)
  • SEKOIA_Ransomware_Lin_Avoslocker_Strings (yara-rule)

Related threat objects

Reports & references

  • advintel.io — Enter Karakurt Data Extortion Arm Of Prolific Ransomware Group (report)
  • blogs.vmware.com — Esxi Targeting Ransomware The Threats That Are After Your Virtual Machines Part 1 (report)
  • news.sophos.com — The Ransomware Threat Intelligence Center (report)
  • Broadcom/Symantec — Sed Fy22Q2 Ses Ransomware Threat Landscape Wp (report)
  • Palo Alto Unit 42 — Emerging Ransomware Groups (report)
  • Broadcom/Symantec — Ransomware Hive Conti Avoslocker (report)
  • advintel.io — Discontinued The End Of Conti S Brand Marks New Chapter For Cybercrime Landscape (report)
  • avertium.com — In Depth Look At Avoslocker Ransomware (report)
  • Palo Alto Unit 42 — Avoslocker Ransomware (report)
  • kroll.com — Avoslocker Ransomware Update (report)
  • picussecurity.com — Avos Locker Ransomware Group (report)
  • brandefense.io — In Depth Analysis Of Avoslocker Ransomware (report)
  • Cisco Talos — Avoslocker New Arsenal (report)
  • techrepublic.com — Avos Ransomware Updates Attack (report)
  • tripwire.com — Avoslocker Ransomware What You Need To Know (report)
  • Trend Micro — Ransomware Spotlight Avoslocker (report)
  • malpedia.caad.fkie.fraunhofer.de — Elf.Avoslocker (report)
  • malpedia.caad.fkie.fraunhofer.de — Win.Avos Locker (report)
  • blogs.blackberry.com — Threat Thursday Avoslocker Prompts Advisory From Fbi And Fincen (report)
  • ic3.gov — 220318 (report)
  • blog.qualys.com — Avoslocker Ransomware Behavior Examined On Windows Linux (report)
  • blog.lexfo.fr — Avoslocker (report)
  • blogs.vmware.com — Avoslocker Modern Linux Ransomware Threats (report)
  • blog.cyble.com — Avoslocker Ransomware Linux Version Targets Vmware Esxi Servers (report)
  • malwarebytes.com — Avoslocker Enters The Ransomware Scene Asks For Partners (report)

External references