Disclosure context

About radar

Radar is an emerging ransomware group that first appeared in September 2025, operating with apparent financial motivations based on their targeting patterns across multiple sectors and countries. The group's origin and affiliations remain unclear due to limited public documentation from established threat intelligence sources, though their geographic targeting suggests a focus on English-speaking nations and select international markets. Based on available victim data, Radar appears to employ opportunistic targeting methods that have successfully compromised 23 organizations across diverse sectors including construction, financial services, transportation/logistics, and technology, with operations spanning the United States, United Kingdom, Australia, Kuwait, and other regions. The group's attack methodology, encryption techniques, and whether they employ double or triple extortion tactics have not been extensively documented by major threat intelligence firms or law enforcement agencies. No significant high-profile campaigns, major ransoms, or law enforcement disruption actions against Radar have been publicly reported by CISA, FBI, or established security research organizations. Given the group's recent emergence and limited public intelligence reporting, Radar's current operational status and long-term capabilities remain under assessment by the cybersecurity community. The group has been linked to 26 public disclosures across our corpus. First observed on a leak site on September 10, 2025; most recent post May 18, 2026. The operation is currently active.

Timeline of this disclosure

October 8, 2025Chek Tan and Company, LLP listed by radaron the group's public leak site

Sector and geography

This disclosure adds to ransomware activity in the Not Found sector, which has 4,859 disclosures indexed across all operators we track. Geographically, Chek Tan and Company, LLP is reported in United States, a country with 7,392 ransomware disclosures in our corpus.

How we know this. Darkfield monitors public ransomware leak sites continuously, archiving every new disclosure and the data later released against the victim. Each entry on this page is sourced from the operator's own publication and cross-checked against complementary OSINT feeds (RansomLook, ransomware.live, RansomWatch). We do not collect or host stolen data — only the metadata, timestamps and screenshots needed to make the public disclosure searchable and accountable. Records here are corrected when the original post is edited, retracted, or merged with another disclosure.

Ransomware victim disclosure

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Chek Tan and Company, LLP

Claimed by radar · listed 7 months ago

Age

since listed · data leaked

Status timeline

Listed
Oct 8, 2025
Data leaked

At a glance

Group: radar
Status: Data leaked
Country: United States
Sector: Not Found
Listed on leak site: Oct 8, 2025

About the victim

AI dossier — public-source company profile

Chek Tan and Company, LLP is an accounting and advisory firm based in San Francisco, California. The firm provides services including accounting, audits, management consulting, IRS representation, and tax management. It operates as a limited liability partnership serving clients in the United States.

Industry: Accounting & Tax Advisory Services
Address: San Francisco, California, United States

Attack summary

Severity: critical — An accounting and tax advisory firm holds highly sensitive regulated financial and personal data (PII, tax returns, IRS records) for its clients at scale. Data has been published, making this a confirmed exfiltration of regulated/sensitive financial and personal information.

The Radar ransomware group claims an attack on Chek Tan and Company, LLP and has published data (disclosed status: data_published), though the specific volume of exfiltrated data and whether encryption occurred are not detailed in the post.

critical

Data the group says was taken

AI dossier — extracted from the leak post

Tax records
Audit files
Financial statements
Client PII
IRS correspondence
Management consulting documents

What the group claims

Chek Tan and Company offers accounting, audits, management consulting, IRS representation, and tax management services. San Francisco, California, United States.

Screenshot of the leak post

Leak screenshot for Chek Tan and Company, LLP

Sources

Victim sitechektan.com

Source

Indexed 7 months ago

This page surfaces a public ransomware disclosure indexed by Darkfield. Original posts come from the operator's own leak site; we cross-check against ransomware.live, RansomLook and RansomWatch where applicable. Share this URL freely.