Cisco Talos Breach Incident Score: Analysis & Impact (CIS5692656111325)

In this Rankiteo incident briefing, we review the Cisco Talos breach identified under incident ID CIS5692656111325.

The analysis begins with a detailed overview of Cisco Talos's information like the linkedin page: https://www.linkedin.com/company/cisco-talos-intelligence-group, the number of followers: 25159, the industry type: Computer and Network Security and the number of employees: 237 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 751 with a difference of -1 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 Cisco Talos and their customers.

On 25 September 2025, Federal Civilian Executive Branch (FCEB) Agencies disclosed Vulnerability Exploitation, Zero-Day Attack and State-Sponsored Cyber Espionage issues under the banner "Active Exploitation of Cisco ASA and Firepower Firewall Vulnerabilities (CVE-2025-20333, CVE-2025-20362)".

CISA has ordered US federal agencies to address two actively exploited zero-day vulnerabilities (CVE-2025-20333, CVE-2025-20362) in Cisco Adaptive Security Appliances (ASA) and Firepower firewalls.

The disruption is felt across the environment, affecting ~32,000 unpatched internet-facing Cisco ASA/Firepower appliances (down from ~48,000).

In response, teams activated the incident response plan, moved swiftly to contain the threat with measures like Firmware updates to patched versions, Decommissioning of legacy/unsupported devices and Network segmentation (implied), and began remediation that includes Mandatory patching by December 3, 2025, Replacement of unsupported hardware and CISA follow-ups with non-compliant agencies, and stakeholders are being briefed through CISA Emergency Directive 25-03 (2025-09-25), Public advisories and Stakeholder notifications.

The case underscores how Ongoing (CISA tracking active exploitation; remediation deadline: 2025-12-03), teams are taking away lessons such as Incomplete patching (e.g., updating to still-vulnerable versions) undermines mitigation efforts, Legacy/unsupported devices pose significant risks and must be decommissioned and State-sponsored actors leverage zero-days for long-term persistence (e.g., ROMMON backdoors), and recommending next steps like Verify firmware versions against CISA’s mitigation guidance to ensure *fully* patched status, Prioritize replacement of end-of-life Cisco ASA/Firepower devices and Implement network segmentation to limit lateral movement, with advisories going out to stakeholders covering CISA directives, Cisco customer notifications and Federal agency internal briefings.

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 high confidence (95%), supported by evidence indicating unpatched Cisco ASA/Firepower appliances (internet-facing) exploited via CVE-2025-20333 (RCE) and Exploitation for Privilege Escalation (T1068) with high confidence (95%), supported by evidence indicating cVE-2025-20362 (Privilege Escalation) used post-initial access. Under the Persistence tactic, the analysis identified Pre-OS Boot: Bootkit (T1542.005) with high confidence (99%), supported by evidence indicating custom malware to disable logging... modify the ROMMON bootloader for persistence and Rootkit (T1014) with high confidence (90%), supported by evidence indicating custom malware with persistent backdoor and anti-forensic capabilities. Under the Privilege Escalation tactic, the analysis identified Exploitation for Privilege Escalation (T1068) with high confidence (95%), supported by evidence indicating cVE-2025-20362 (Privilege Escalation) enables higher-level access. Under the Defense Evasion tactic, the analysis identified Indicator Blocking: Disable Logging (T1562.006) with high confidence (99%), supported by evidence indicating custom malware to disable logging, prevent forensic analysis, Indicator Removal: File Deletion (T1070.004) with high confidence (90%), supported by evidence indicating crash dump prevention to evade detection, and Use Alternate Authentication Material: Pass the Hash (T1550.002) with moderate to high confidence (70%), supported by evidence indicating lateral movement across networks implies credential reuse/post-exploitation. Under the Credential Access tactic, the analysis identified OS Credential Dumping: LSASS Memory (T1003.001) with moderate to high confidence (80%), supported by evidence indicating lateral movement suggests credential harvesting post-exploitation. Under the Lateral Movement tactic, the analysis identified Remote Services: Remote Desktop Protocol (T1021.001) with moderate to high confidence (70%), supported by evidence indicating risk of lateral movement across networks via compromised appliances and Remote Services: SSH (T1021.004) with moderate to high confidence (70%), supported by evidence indicating lateral movement in enterprise environments often leverages SSH. Under the Collection tactic, the analysis identified Data from Local System (T1005) with moderate to high confidence (80%), supported by evidence indicating potential data exfiltration via backdoor implies local data staging. Under the Exfiltration tactic, the analysis identified Exfiltration Over C2 Channel (T1041) with high confidence (90%), supported by evidence indicating potential data exfiltration via custom backdoor. Under the Impact tactic, the analysis identified Endpoint Denial of Service: Application or System Exploitation (T1499.004) with moderate to high confidence (80%), supported by evidence indicating potential disruption of federal agency networks via exploited appliances. These correlations help security teams understand the attack chain and develop appropriate defensive measures based on the observed tactics and techniques.