Checkout.com Breach Incident Score: Analysis & Impact (CHE3702137111525)

In this Rankiteo incident briefing, we review the Checkout.com breach identified under incident ID CHE3702137111525.

The analysis begins with a detailed overview of Checkout.com's information like the linkedin page: https://www.linkedin.com/company/checkout, the number of followers: 262397, the industry type: Financial Services and the number of employees: 2214 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 770 and after the incident was 654 with a difference of -116 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 Checkout.com and their customers.

On 01 November 2025, Checkout.com disclosed data breach and ransomware extortion attempt issues under the banner "Checkout.com Ransomware Extortion Attempt by ShinyHunters (November 2025)".

Checkout.com was targeted by a digital extortion attempt by the threat actor group ShinyHunters in November 2025.

The disruption is felt across the environment, affecting legacy third-party cloud file storage, and exposing internal operation documents and merchant onboarding materials (pre-2021).

In response, teams activated the incident response plan, and began remediation that includes contacting impacted customers and coordinating with regulators, and stakeholders are being briefed through public apology by CTO, transparency in disclosure and donation to cybersecurity research centers.

The case underscores how ongoing (coordinating with law enforcement and regulators), teams are taking away lessons such as Importance of proper decommissioning of legacy systems, transparency in incident response, and refusal to fund criminal activity through ransom payments, and recommending next steps like ensure thorough decommissioning of legacy systems, invest in cybersecurity research and collaboration with academic institutions and maintain transparency with stakeholders during incidents, with advisories going out to stakeholders covering public statement by CTO Mariano Albera and contacting impacted merchants.

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 to high confidence (85%), with evidence including legacy third-party cloud file storage system (improperly decommissioned), and vulnerability exploited such as improper decommissioning of legacy cloud storage and Valid Accounts: Cloud Accounts (T1078.004) with moderate to high confidence (70%), supported by evidence indicating legacy third-party cloud file storage system (potential misuse of residual credentials). Under the Persistence tactic, the analysis identified Account Manipulation: Cloud Accounts (T1098.003) with moderate confidence (60%), supported by evidence indicating legacy third-party cloud file storage system (possible residual access retention). Under the Defense Evasion tactic, the analysis identified Impair Defenses: Disable or Modify Cloud Logs (T1562.001) with moderate confidence (50%), supported by evidence indicating improper decommissioning (suggests logging/monitoring gaps in legacy system). Under the Credential Access tactic, the analysis identified Unsecured Credentials: Credentials In Files (T1552.001) with moderate to high confidence (75%), supported by evidence indicating legacy third-party cloud file storage (potential hardcoded credentials in decommissioned system). Under the Discovery tactic, the analysis identified File and Directory Discovery (T1083) with moderate to high confidence (80%), supported by evidence indicating exposing internal operation documents and merchant onboarding materials. Under the Collection tactic, the analysis identified Data from Local System (T1005) with high confidence (90%), with evidence including data exfiltration such as true, and internal operation documents, merchant onboarding materials. Under the Exfiltration tactic, the analysis identified Exfiltration Over Alternative Protocol: Exfiltration Over Cloud Storage API (T1048.003) with high confidence (95%), supported by evidence indicating data exfiltration such as true via legacy third-party cloud file storage system. Under the Impact tactic, the analysis identified Data Encrypted for Impact (T1486) with lower confidence (30%), supported by evidence indicating ransomware extortion attempt (though data encryption such as false) and Data Theft for Extortion (T1659) with high confidence (100%), with evidence including ransomware extortion attempt with data exfiltration such as true, and ransom demanded such as true, ransom paid such as false. These correlations help security teams understand the attack chain and develop appropriate defensive measures based on the observed tactics and techniques.