Incident Score: Analysis & Impact (GIT1779459975)
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Rankiteo Score Impact Analysis
Key Highlights From The Incident Analysis
- Timeline of GitHub'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 GitHub 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 GitHub breach identified under incident ID GIT1779459975.
The analysis begins with a detailed overview of GitHub's information like the linkedin page: https://www.linkedin.com/company/github, the number of followers: 5688458, the industry type: Software Development and the number of employees: 6007 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 100 and after the incident was 100 with a difference of 0 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 GitHub and their customers.
On 18 May 2026, Tiledesk disclosed Supply Chain Attack issues under the banner "Megalodon Attack Targets 5,500+ GitHub Repositories".
A large-scale automated attack dubbed 'Megalodon' compromised 5,561 GitHub repositories by pushing 5,718 malicious code updates within a six-hour window.
The disruption is felt across the environment, affecting GitHub Repositories and npm Packages, and exposing Cloud credentials (AWS, Google Cloud, Microsoft Azure), System logs and Code files.
Formal response steps have not been shared publicly yet.
The case underscores how teams are taking away lessons such as The incident underscores the growing sophistication of supply-chain attacks targeting open-source ecosystems, with developers and organizations facing heightened risks from automated, large-scale breaches.
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 Dependencies and Development Tools (T1195.001) with high confidence (90%), with evidence including 5,718 malicious code updates pushed to 5,561 GitHub repositories, and malicious VS Code extension compromised 3,800 repositories, Trusted Relationship (T1199) with moderate to high confidence (80%), supported by evidence indicating attackers mimicked official automated services (e.g., build-bot@, auto-ci@), and Valid Accounts: Cloud Accounts (T1078.004) with moderate to high confidence (70%), supported by evidence indicating gitHub Actions tokens stolen, allowing impersonation of legitimate workflows. Under the Execution tactic, the analysis identified Command and Scripting Interpreter: JavaScript (T1059.007) with moderate to high confidence (80%), supported by evidence indicating 111-line background script executed to exfiltrate data to C2 server and Serverless Execution (T1648) with moderate to high confidence (70%), supported by evidence indicating malicious .github/workflows/ci.yml triggered data-stealing script on updates. Under the Persistence tactic, the analysis identified Boot or Logon Autostart Execution: XDG Autostart Entries (T1547.013) with moderate confidence (60%), supported by evidence indicating dormant backdoors replaced system files, activated later via GitHub API and Hijack Execution Flow: LD_PRELOAD (T1574.006) with moderate confidence (50%), supported by evidence indicating optimize-Build technique replaced existing system files with backdoors. Under the Privilege Escalation tactic, the analysis identified Abuse Elevation Control Mechanism: Setuid and Setgid (T1548.001) with moderate confidence (60%), supported by evidence indicating gitHub Actions tokens allowed unauthorized access to cloud environments. Under the Defense Evasion tactic, the analysis identified Masquerading: Match Legitimate Name or Location (T1036.005) with high confidence (90%), supported by evidence indicating fake GitHub accounts with randomized names mimicked official services, Hide Artifacts: Hidden Window (T1564.003) with moderate to high confidence (70%), supported by evidence indicating hidden backdoors embedded in legitimate files, evading detection, and Obfuscated Files or Information: Binary Padding (T1027.001) with moderate confidence (60%), supported by evidence indicating dormant backdoors activated later to avoid detection. Under the Credential Access tactic, the analysis identified Steal Application Access Token (T1528) with high confidence (90%), supported by evidence indicating gitHub Actions tokens stolen, allowing impersonation of workflows, Unsecured Credentials: Credentials In Files (T1552.001) with moderate to high confidence (80%), supported by evidence indicating cloud credentials (AWS, Google Cloud, Azure) harvested by malware, and Unsecured Credentials: Private Keys (T1552.004) with moderate to high confidence (80%), supported by evidence indicating 30 types of private keys exfiltrated to C2 server. Under the Discovery tactic, the analysis identified Account Discovery: Cloud Account (T1087.004) with moderate to high confidence (70%), supported by evidence indicating attackers targeted repositories with cloud credentials and File and Directory Discovery (T1083) with moderate confidence (60%), supported by evidence indicating system logs and code files exfiltrated by malware. Under the Collection tactic, the analysis identified Data from Local System (T1005) with high confidence (90%), supported by evidence indicating system logs, code files, and private keys collected by malware and Data from Code Repositories (T1213.003) with high confidence (90%), supported by evidence indicating 5,561 GitHub repositories compromised for data theft. Under the Command and Control tactic, the analysis identified Application Layer Protocol: Web Protocols (T1071.001) with moderate to high confidence (80%), supported by evidence indicating data exfiltrated to C2 server at 216.126.225.129 such as 8443. Under the Exfiltration tactic, the analysis identified Exfiltration Over C2 Channel (T1041) with high confidence (90%), supported by evidence indicating sensitive data exfiltrated to 216.126.225.129 such as 8443 via background script and Transfer Data to Cloud Account (T1537) with moderate to high confidence (70%), supported by evidence indicating cloud credentials harvested, enabling unauthorized cloud access. Under the Impact tactic, the analysis identified Resource Hijacking (T1496) with moderate to high confidence (70%), supported by evidence indicating gitHub Actions tokens used to impersonate legitimate workflows and Data Destruction (T1485) with lower confidence (40%), supported by evidence indicating malicious code updates could corrupt or destroy repository data. These correlations help security teams understand the attack chain and develop appropriate defensive measures based on the observed tactics and techniques.
Sources & References
- GitHub Rankiteo Cyber Incident Details: https://www.rankiteo.com/company/github/incident/GIT1779459975
- GitHub CyberSecurity Rating page: https://www.rankiteo.com/company/github
- GitHub Rankiteo Cyber Incident Blog Article: https://blog.rankiteo.com/git1779459975-github-cyber-attack-may-2026/
- GitHub CyberSecurity Score History: https://www.rankiteo.com/company/github/history
- GitHub CyberSecurity Incident Source: https://hackread.com/github-repositories-megalodon-supply-chain-attack/
- 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