Atomsilo Ransomware
TrackedThreat actor group tracked in the global ransomware database · Last disclosure: Feb 24, 2026
ThreatAI Analysis
Compiled from the ransomware.live profile for Atomsilo and from this database. Figures and technique mappings are quoted from the source data, not inferred.
Who Atomsilo is
AtomSilo is a double-extortion ransomware group that emerged in September 2021, exploiting the Atlassian Confluence vulnerability (CVE-2021-26084) for initial access and demanding ransoms up to $1 million, attributed to the Chinese state-linked threat actor BRONZE STARLIGHT.
Recorded activity
Disclosures attributed to Atomsilo in this database run from February 2026 to February 2026, totalling 1 victims — 0% of everything tracked here.
Indicators of compromise
Showing a sample of 1 EMAIL on file. Hashes and network indicators published for Atomsilo. Leak-site addresses are deliberately excluded. Indicators age quickly — treat a match as a starting point for investigation, and an absence of matches as no assurance.
YARA detection rules
atomsilo.yar
/*
AtomSilo ransomware
*/
rule AtomSilo_Ransomnote
{
meta:
author = "ransomware.live"
family = "ransomware.atomsilo"
description = "Detects AtomSilo ransomware ransom note"
date = "2026-05-04"
severity = 7
score = 70
strings:
$s1 = "AtomSilo" ascii nocase
$s2 = "ATOMSILO" ascii
$s3 = "README-FILE.hta" ascii nocase
condition:
any of them
}Community-contributed rules for Atomsilo, reproduced as published. Test them against your own corpus before relying on them: rule quality and false-positive behaviour vary by author.
Threat Actor Analysis
Atomsilo is a ransomware threat group that has disclosed 1 victims in publicly accessible leak site data, representing 0% of all ransomware attacks tracked in this database. The earliest victim disclosure attributed to Atomsilo in our dataset dates to February 2026.
Industry-wise, Atomsilo shows a concentration in the Financial Services sector. These industries are frequently targeted because they manage sensitive data, critical operations, or have lower tolerance for operational downtime — conditions that increase ransom payment likelihood.
Like most modern ransomware operations, Atomsilo likely employs a double extortion model: encrypting victim files while simultaneously exfiltrating data, creating dual pressure to pay the ransom. Victim organisations that refuse payment face having their data published on the group's dark web leak site.
Note: This profile is generated from public leak site disclosures aggregated via the ransomware.live API. Data is updated automatically. The table below lists the 1 most recent of the 1 disclosures we hold for this group; use the link beneath it to page through all of them.
Recent Victim Disclosures (showing 1 of 1)
| # | Organization | Country | Sector | Date |
|---|---|---|---|---|
| 1 | A large bank in Asia bank.com | — | Financial Services | Feb 24, 2026 |
Frequently Asked Questions
What is Atomsilo ransomware?
Atomsilo is a ransomware threat group that has claimed 1 victims since its first known activity in February 2026. The group operates by infiltrating target networks, exfiltrating data, encrypting files, and threatening to publish stolen data on a dark web leak site if the ransom is not paid.
How many victims has Atomsilo attacked?
Atomsilo has claimed 1 victims in our database, representing 0% of all tracked ransomware attacks.
Which countries does Atomsilo target?
Atomsilo has attacked organizations in 0 countries.
Which industries does Atomsilo target?
Atomsilo most frequently targets the Financial Services sectors based on victim disclosures in our database.
Is Atomsilo still active?
Atomsilo's most recent victim disclosure in our database was on February 24, 2026. Ransomware groups frequently rebrand or go dormant; monitor this page and our ransomware map for the latest activity.