AT&T Breach Incident Score: Analysis & Impact (ATT0893608111425)

In this Rankiteo incident briefing, we review the AT&T breach identified under incident ID ATT0893608111425.

The analysis begins with a detailed overview of AT&T's information like the linkedin page: https://www.linkedin.com/company/att, the number of followers: 1591781, the industry type: Telecommunications and the number of employees: 177538 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 260 and after the incident was 179 with a difference of -81 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 AT&T and their customers.

AT&T Inc. recently reported "AT&T Data Breaches Settlement (2024)", a noteworthy cybersecurity incident.

AT&T Inc.

The disruption is felt across the environment, and exposing Social Security numbers, Birthdates and Phone records, with nearly Millions (nearly all of AT&T’s customer base) records at risk, plus an estimated financial loss of $177 million (settlement amount).

In response, teams activated the incident response plan, and began remediation that includes Improved encryption and Enhanced monitoring, while recovery efforts such as $177 million settlement fund, Free credit monitoring and identity theft protection (up to 3 years) and Reimbursement for documented losses (up to $7,500 per person) continue, and stakeholders are being briefed through Official settlement website (managed by Kroll), Public awareness campaigns and Social media outreach (e.g., X/Twitter).

The case underscores how Resolved (settlement approved by federal judge in Texas), teams are taking away lessons such as Legacy systems in telecommunications are highly vulnerable to sophisticated cyber threats, Proactive investments in zero-trust architectures and AI-driven threat detection are critical and Settlements, while costly, may not fully deter negligence if penalties are proportionally small compared to corporate revenues, and recommending next steps like Telecom firms should prioritize upgrading security protocols to prevent similar breaches, Implement stricter breach notification timelines and regulatory compliance measures and Invest in AI-driven threat detection and zero-trust architectures, with advisories going out to stakeholders covering Customers advised to file claims by December 18, 2025 (extended deadline), Free credit monitoring and identity theft protection offered for up to 3 years and Documentation required for reimbursement of losses exceeding basic claim amounts.

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 Valid Accounts: Cloud Accounts (T1078.004) with moderate to high confidence (70%), supported by evidence indicating sophisticated hacking attempts exploited outdated security protocols and Exploit Public-Facing Application (T1190) with moderate to high confidence (80%), supported by evidence indicating outdated security protocols and data leaked on dark web (March breach). Under the Exfiltration tactic, the analysis identified Exfiltration Over Alternative Protocol: Exfiltration to Cloud Storage (T1048.003) with high confidence (90%), supported by evidence indicating data leaked on dark web (March) and illegally downloaded (July) and Automated Exfiltration (T1020) with moderate to high confidence (80%), supported by evidence indicating millions of records exfiltrated in both breaches. 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 outdated security protocols and inadequate encryption likely exposed credentials. Under the Impact tactic, the analysis identified Data Destruction (T1485) with lower confidence (30%), supported by evidence indicating no direct evidence, but illegally downloaded suggests potential data manipulation, Data Encrypted for Impact (T1486) with lower confidence (20%), supported by evidence indicating no ransomware mentioned, but inadequate encryption implies risk of post-compromise encryption, and Identity Theft (T1659) with high confidence (95%), supported by evidence indicating high identity theft risk due to exposed SSNs, birthdates, and PII. Under the Defense Evasion tactic, the analysis identified Indicator Removal: File Deletion (T1070.004) with moderate confidence (60%), supported by evidence indicating no logs/forensics mentioned; outdated monitoring suggests evasion of detection and Impair Defenses: Disable or Modify Tools (T1562.001) with moderate to high confidence (70%), supported by evidence indicating inadequate monitoring implies defenders were impaired or bypassed. Under the Persistence tactic, the analysis identified Account Manipulation: Additional Cloud Credentials (T1098.003) with moderate confidence (65%), supported by evidence indicating sophisticated hacking attempts may have involved credential persistence. Under the Collection tactic, the analysis identified Data from Local System (T1005) with high confidence (90%), supported by evidence indicating social Security numbers, birthdates, phone records collected from AT&T systems. These correlations help security teams understand the attack chain and develop appropriate defensive measures based on the observed tactics and techniques.