Incident Score: Analysis & Impact (SOCSIC1780057768)
The details regarding individual company incidents & reports gives you full view from every side.
Rankiteo Score Impact Analysis
Key Highlights From The Incident Analysis
- Timeline of Sicoob's Cyber Attack and lateral movement inside company's environment.
- Overview of affected data sets, including SSNs and PHI, and why they materially increase incident severity.
- How Rankiteo’s incident engine converts technical details into a normalized incident score.
- How this cyber incident impacts Sicoob Rankiteo cyber scoring and cyber rating.
- Rankiteo’s MITRE ATT&CK correlation analysis for this incident, with associated confidence level.
Full Incident Analysis Transcript
In this Rankiteo incident briefing, we review the Sicoob breach identified under incident ID SOCSIC1780057768.
The analysis begins with a detailed overview of Sicoob's information like the linkedin page: https://www.linkedin.com/company/sicooboficial, the number of followers: 2217532, the industry type: Financial Services and the number of employees: 15441 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 807 and after the incident was 793 with a difference of -14 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 Sicoob and their customers.
On 06 May 2026, Sicoob disclosed Supply Chain Attack issues under the banner "Sophisticated Supply Chain Attack Targets Brazilian Banking SDK via Malicious NuGet Package".
A supply chain attack impersonating the official C# SDK for Sicoob, one of Brazil’s largest cooperative banking networks, was uncovered by researchers at Socket.
The disruption is felt across the environment, affecting Production environments using Sicoob.Sdk (versions 2.0.0–2.0.4), and exposing Banking credentials, payment data, PFX certificates, plaintext passwords, client IDs, boleto API responses (transaction details, payer/payee information, due dates, payment status).
In response, moved swiftly to contain the threat with measures like Malicious package blocked following abuse report.
The case underscores how Ongoing.
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.
MITRE ATT&CK® Correlation Analysis
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 Supply Chain Compromise: Compromise Software Supply Chain (T1195.002) with high confidence (95%), supported by evidence indicating malicious NuGet package, Sicoob.Sdk (versions 2.0.0–2.0.4), contained hidden credential exfiltration logic and Phishing: Spearphishing Link (T1566.002) with moderate to high confidence (70%), supported by evidence indicating google’s AI search briefly promoted Sicoob.Sdk as the recommended .NET integration path. Under the Execution tactic, the analysis identified User Execution: Malicious File (T1204.002) with high confidence (90%), supported by evidence indicating developers initialized SicoobClient with client ID, PFX file path, and password. Under the Credential Access tactic, the analysis identified Unsecured Credentials: Private Keys (T1552.004) with high confidence (95%), supported by evidence indicating dLL secretly base64-encoded the PFX certificate and transmitted it with plaintext password and client ID and Input Capture: Keylogging (T1056.001) with moderate to high confidence (80%), supported by evidence indicating captured raw boleto API responses, exposing transaction details, payer/payee information. Under the Collection tactic, the analysis identified Data from Local System (T1005) with high confidence (90%), supported by evidence indicating exfiltrated PFX certificates, plaintext passwords, client IDs, and boleto API responses and Automated Collection (T1119) with moderate to high confidence (85%), supported by evidence indicating exfiltration activated when isSandbox was set to false, targeting production environments. Under the Exfiltration tactic, the analysis identified Exfiltration Over C2 Channel (T1041) with high confidence (95%), supported by evidence indicating transmitted data to hardcoded Sentry telemetry endpoint (o4511335034847232.ingest.de.sentry.io) and Exfiltration Over Web Service: Exfiltration to Cloud Storage (T1567.002) with moderate to high confidence (80%), supported by evidence indicating used Sentry telemetry endpoint for data exfiltration. Under the Defense Evasion tactic, the analysis identified Masquerading: Match Legitimate Name or Location (T1036.005) with high confidence (95%), supported by evidence indicating package mimicked legitimate .NET 8 SDK for Sicoob’s APIs, with GitHub organization (Sicoob-Cooperativa) and Obfuscated Files or Information: Binary Padding (T1027.001) with moderate to high confidence (70%), supported by evidence indicating compiled DLL contained malicious logic absent from the public repository. Under the Command and Control tactic, the analysis identified Application Layer Protocol: Web Protocols (T1071.001) with high confidence (90%), supported by evidence indicating exfiltrated data to Sentry telemetry endpoint via web protocols. These correlations help security teams understand the attack chain and develop appropriate defensive measures based on the observed tactics and techniques.
Sources & References
- Sicoob Rankiteo Cyber Incident Details: https://www.rankiteo.com/company/sicooboficial/incident/SOCSIC1780057768
- Sicoob CyberSecurity Rating page: https://www.rankiteo.com/company/sicooboficial
- Sicoob Rankiteo Cyber Incident Blog Article: https://blog.rankiteo.com/socsic1780057768-nuget-sicoob-cyber-attack-may-2026/
- Sicoob CyberSecurity Score History: https://www.rankiteo.com/company/sicooboficial/history
- Sicoob CyberSecurity Incident Source: https://cyberpress.org/malicious-nuget-package-sicoob-sdk/
- Rankiteo A.I CyberSecurity Rating methodology: https://www.rankiteo.com/Images/rankiteo_algo.pdf
- Rankiteo TPRM Scoring methodology: https://static.rankiteo.com/model/rankiteo_tprm_methodology.pdf