Was Lisa Mayer CA, Professional Corporation hit by ransomware?

Lisa Mayer CA, Professional Corporation was listed by the alphv ransomware operation (Canada), and stolen data was published on the group's leak site. Darkfield tracks this disclosure with the original leak post, screenshot and group context.

Who is the alphv ransomware group?

alphv is a ransomware operator tracked by Darkfield. See the full operator dossier for its known victims, sectors targeted, IOCs and leak-site infrastructure.

What data was leaked in the Lisa Mayer CA, Professional Corporation breach?

alphv published data attributed to Lisa Mayer CA, Professional Corporation. Darkfield captured the leak post and a screenshot of the listing.

Ransomware victim disclosure

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Lisa Mayer CA, Professional Corporation

Claimed by Alphv · listed 3 years ago

31m

Age

since listed · data leaked

Status timeline

ListedDec 2, 2023
Data leakeddate unknown

At a glance

Group: Alphv
Status: Data leaked
Country: Canada
Sector: Business Services
Listed on leak site: Dec 2, 2023

About the victim

AI dossier — public-source company profile

Lisa Mayer CA, Professional Corporation is an accounting firm based in Sarnia, Canada, offering taxation, accounting, bookkeeping, payroll processing, and related professional services. The firm emphasizes client relationships, cost savings optimization, and regulatory compliance support.

Industry: Accounting & Tax Services

Attack summary

Severity: high — Confirmed data exfiltration and publication by ALPHV. Accounting firm data typically includes sensitive financial and tax information for multiple clients, and exposure at scale poses significant regulatory and privacy risks.

ALPHV claims to have exfiltrated data from the firm. The group has published data but no specific details on data types or volume are provided in the leak post.

high

Data the group says was taken

AI dossier — extracted from the leak post

Client financial records
Tax documents
Payroll information
Accounting records
Business correspondence

What the group claims

Lisa Mayer and her team are dedicated to delivering top-notch services, all while fostering strong and transparent connections with each and every client. Their overarching goal is to furnish invaluable professional guidance, support, and a sense of assurance to empower their clients to prosper. They excel in providing dependable and punctual support, with a specialization in helping clients achieve cost savings and regulatory compliance. Their proficient team offers a wide array of services encompassing Taxation, Accounting, Bookkeeping, Payroll, and more.

Sources

Victim sitecpasarnia.ca
Leak posthttp://alphvmmm27o3abo3r2mlmjrpdmzle3rykajqc5xsj7j7ejksbpsa36ad.onion/60036b13-72e8-4e13-b423-bc0c0cded923

Source

Indexed 3 years 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.

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Disclosure context

About alphv

ALPHV, also known as BlackCat or Noberus, is a financially motivated ransomware group that emerged in September 2021 and rapidly established itself as one of the most sophisticated and prolific ransomware operations observed by researchers at Mandiant, CISA, and the FBI. The group is suspected to have Russian-speaking origins and operates as a Ransomware-as-a-Service (RaaS) platform, with well-documented links to former affiliates of the DarkSide and BlackMatter ransomware operations, suggesting a continuity of personnel and tradecraft across these successive rebrand events. ALPHV is technically distinguished by its use of Rust-based ransomware — an uncommon choice at the time of its emergence — which enabled cross-platform attacks against Windows, Linux, and VMware ESXi environments; the group employs multiple initial access vectors including compromised credentials, phishing, and exploitation of unpatched vulnerabilities, and routinely conducts double and triple extortion by exfiltrating sensitive data prior to encryption and threatening victims with public disclosure on their dedicated leak site, with some cases involving additional pressure through direct contact with victim customers and regulators. ALPHV has claimed responsibility for high-profile attacks against MGM Resorts International, Caesars Entertainment, Reddit, and healthcare provider Change Healthcare — the latter representing one of the most disruptive cyberattacks on the U.S. healthcare sector on record, with a reported ransom payment of approximately $22 million — and has accumulated over 731 known victims across the United States, Canada, Australia, the United Kingdom, and Germany, with particular concentration in business services, manufacturing, healthcare, technology, and financial services sectors. In December 2023, the FBI and international partners conducted a disruption operation against ALPHV's infrastructure and released a decryption tool for victims; however, the group subsequently attempted to rebrand and continued operations before an apparent final collapse in March 2024, following an alleged exit scam against affiliates after the Change Healthcare ransom payment, with law enforcement officially attributing the group's infrastructure seizure shortly thereafter. The group has been linked to 731 public disclosures across our corpus. First observed on a leak site on September 9, 2021; most recent post March 3, 2024. The operation is currently inactive.

Also tracked as: BlackCat, Noberus.

Timeline of this disclosure

December 2, 2023Lisa Mayer CA, Professional Corporation listed by alphvon the group's public leak site

Other recent disclosures by alphv

alphv has been linked to 731 public victims on Darkfield. A sample of the most recent:

See the full alphv dossier →

Sector and geography

This disclosure adds to ransomware activity in the Business Services sector, which has 3,796 disclosures indexed across all operators we track. Geographically, Lisa Mayer CA, Professional Corporation is reported in Canada, a country with 314 ransomware disclosures in our corpus.

If your organisation is affected

A listing by alphv means Lisa Mayer CA, Professional Corporation appeared on a ransomware extortion site and data attributed to it has been published. If this is your organisation, or a supplier you depend on, the priority is to confirm the intrusion and contain it before the window to act closes.

Engage your incident-response team and preserve forensic evidence before remediating — do not wipe affected systems first.
Force a password reset and revoke active sessions for exposed accounts; rotate any credentials, API keys or certificates that may have been in the stolen data.
Assess regulatory notification duties (GDPR, NIS2, sector regulators) — many carry a 72-hour reporting clock from awareness.
Report the incident to your national CERT, CCCS (Canada), as required for your jurisdiction.
Monitor for the data appearing on alphv's leak site and across paste and breach channels, and brief downstream partners who may be exposed through you.

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.