Incident Score: Analysis & Impact (CAL1770166797)
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 Callstack'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 Callstack 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 Callstack breach identified under incident ID CAL1770166797.
The analysis begins with a detailed overview of Callstack's information like the linkedin page: https://www.linkedin.com/company/callstack, the number of followers: 8553, the industry type: IT Services and IT Consulting and the number of employees: 206 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 735 with a difference of -17 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 Callstack and their customers.
On 21 December 2025, a cybersecurity incident called "Hackers Exploit Critical React Native Metro Vulnerability (CVE-2025-11953) for Cross-Platform Attacks" came to light.
A critical vulnerability in the Metro server for React Native (CVE-2025-11953) is being actively exploited by threat actors to deliver malicious payloads on Windows and Linux systems.
The disruption is felt across the environment, affecting Windows, Linux.
In response, and began remediation that includes Patch to @react-native-community/cli-server-api version 20.0.0.
The case underscores how Ongoing, and recommending next steps like Patch affected systems to @react-native-community/cli-server-api version 20.0.0. Monitor for exposed Metro servers and restrict network access to development environments.
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 Exploit Public-Facing Application (T1190) with high confidence (90%), with evidence including exploited via crafted POST request to `/open-url` endpoint, and affects @react-native-community/cli-server-api versions 4.8.0-20.0.0-alpha.2. Under the Execution tactic, the analysis identified Command and Scripting Interpreter: PowerShell (T1059.001) with high confidence (90%), supported by evidence indicating delivered base-64 encoded PowerShell payloads via HTTP POST requests and Exploitation for Client Execution (T1203) with moderate to high confidence (80%), supported by evidence indicating executed arbitrary OS commands via unsanitized user-supplied URLs. Under the Defense Evasion tactic, the analysis identified Impair Defenses: Disable or Modify Tools (T1562.001) with high confidence (90%), supported by evidence indicating disabled endpoint protections by adding Microsoft Defender exclusion paths, Obfuscated Files or Information: Software Packing (T1027.002) with moderate to high confidence (80%), supported by evidence indicating rust-based UPX-packed binary with anti-analysis features, and Masquerading: Match Legitimate Name or Location (T1036.005) with moderate to high confidence (70%), supported by evidence indicating used oversized argument string to evade detection. Under the Command and Control tactic, the analysis identified Application Layer Protocol: Web Protocols (T1071.001) with high confidence (90%), supported by evidence indicating established raw TCP connection to attacker-controlled infrastructure and Ingress Tool Transfer (T1105) with high confidence (90%), supported by evidence indicating downloaded and executed second-stage payload from attacker infrastructure. Under the Discovery tactic, the analysis identified Active Scanning: Vulnerability Scanning (T1595.002) with moderate to high confidence (80%), supported by evidence indicating scans using ZoomEye identified ~3,500 exposed Metro servers. These correlations help security teams understand the attack chain and develop appropriate defensive measures based on the observed tactics and techniques.
Sources & References
- Callstack Rankiteo Cyber Incident Details: https://www.rankiteo.com/company/callstack/incident/CAL1770166797
- Callstack CyberSecurity Rating page: https://www.rankiteo.com/company/callstack
- Callstack Rankiteo Cyber Incident Blog Article: https://blog.rankiteo.com/cal1770166797-organizations-using-react-native-metro-cyber-attack-december-2025/
- Callstack CyberSecurity Score History: https://www.rankiteo.com/company/callstack/history
- Callstack CyberSecurity Incident Source: https://www.bleepingcomputer.com/news/security/hackers-use-critical-react-native-metro-bug-to-breach-dev-systems/
- 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