ZenLedger Breach Incident Score: Analysis & Impact (WALZEN1769189829)

In this Rankiteo incident briefing, we review the ZenLedger breach identified under incident ID WALZEN1769189829.

The analysis begins with a detailed overview of ZenLedger's information like the linkedin page: https://www.linkedin.com/company/zenledger-io, the number of followers: 2597, the industry type: Financial Services and the number of employees: 20 employees

After the initial compromise, the video explains how Rankiteo's incident engine converts technical details into a normalized incident score. The incident score before the incident was 752 and after the incident was 659 with a difference of -93 which is could be a good indicator of the severity and impact of the incident.

In the next step of the video, we will analyze in more details the incident and the impact it had on ZenLedger and their customers.

On 23 January 2026, Waltio disclosed Data Breach issues under the banner "French Crypto Tax Platform Waltio Data Breach Exposes 5,000 Users".

On December 24, 2025, dark web intelligence firm Brinztech identified a database containing the personal data of approximately 5,000 French cryptocurrency holders listed for sale.

The disruption is felt across the environment, and exposing Emails, tax report summaries (potentially names and phone numbers), with nearly 5000 records at risk.

In response, teams activated the incident response plan, and stakeholders are being briefed through Security notice issued to users, CNIL notified, warnings about impersonation scams.

The case underscores how Ongoing, teams are taking away lessons such as Risks faced by crypto tax platforms handling sensitive transaction data under international reporting requirements; importance of verifying security codes in official communications to prevent impersonation scams, and recommending next steps like Enhanced monitoring for unauthorized access, user education on impersonation scams, and stricter data collection policies to avoid storing unnecessary personal information, with advisories going out to stakeholders covering French authorities warned about criminals impersonating law enforcement to target victims; advised users to verify security codes in official communications.

Finally, we try to match the incident with the MITRE ATT&CK framework to see if there is any correlation between the incident and the MITRE ATT&CK framework.

The MITRE ATT&CK framework is a knowledge base of techniques and sub-techniques that are used to describe the tactics and procedures of cyber adversaries. It is a powerful tool for understanding the threat landscape and for developing effective defense strategies.

Rankiteo's analysis has identified several MITRE ATT&CK tactics and techniques associated with this incident, each with varying levels of confidence based on available evidence. Under the Initial Access tactic, the analysis identified Exploit Public-Facing Application (T1190) with moderate confidence (60%), supported by evidence indicating attack described as particularly sophisticated and Trusted Relationship (T1199) with moderate confidence (50%), supported by evidence indicating crypto tax platform handling sensitive transaction data. Under the Credential Access tactic, the analysis identified Unsecured Credentials (T1552) with lower confidence (40%), supported by evidence indicating no passwords or wallet addresses compromised (implies potential access). Under the Collection tactic, the analysis identified Data from Local System (T1005) with moderate to high confidence (80%), supported by evidence indicating emails and summary details from 2024 tax reports compromised and Data from Information Repositories (T1213) with moderate to high confidence (70%), supported by evidence indicating tax report summaries accessed from crypto tax platform. Under the Exfiltration tactic, the analysis identified Exfiltration Over C2 Channel (T1041) with high confidence (90%), supported by evidence indicating database listed for sale on dark web by Brinztech and Exfiltration Over Web Service (T1567) with moderate confidence (60%), supported by evidence indicating data breach exposed 5,000 users personal data. Under the Impact tactic, the analysis identified Defacement (T1491) with lower confidence (30%), supported by evidence indicating extortion attempt received by Waltio and Data Encrypted for Impact (T1486) with lower confidence (20%), supported by evidence indicating no details on encryption, but extortion attempt implies impact. Under the Command and Control tactic, the analysis identified Application Layer Protocol (T1071) with moderate confidence (50%), supported by evidence indicating sophisticated attack implies potential C2 communication. These correlations help security teams understand the attack chain and develop appropriate defensive measures based on the observed tactics and techniques.