SonicWall Breach Incident Score: Analysis & Impact (SON3832338111925)

In this Rankiteo incident briefing, we review the SonicWall breach identified under incident ID SON3832338111925.

The analysis begins with a detailed overview of SonicWall's information like the linkedin page: https://www.linkedin.com/company/SonicWall, the number of followers: 111355, the industry type: Computer and Network Security and the number of employees: 1922 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 676 and after the incident was 676 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 SonicWall and their customers.

On 01 October 2025, SonicWall disclosed Ransomware, Credential Stuffing and Zero-Day Exploits issues under the banner "Q3 2025 Ransomware Surge and VPN Credential Exploits".

Ransomware attacks surged in Q3 2025, with Akira, Qilin, and INC Ransomware groups accounting for 65% of cases.

The disruption is felt across the environment, affecting SonicWall SSLVPN Appliances, Microsoft SharePoint and CrushFTP Servers, and exposing VPN Credentials, Corporate Data (via Ransomware) and Potential PII (via Infostealers).

In response, teams activated the incident response plan, moved swiftly to contain the threat with measures like Temporary Mitigations for Zero-Days, Network Access Lockdowns and Credential Rotation (for VPNs), and began remediation that includes Patch Management for Zero-Days (CVE-2025-*), MFA Enforcement for VPNs and Access Control Hardening (Lockout Policies), and stakeholders are being briefed through Beazley Security Advisories and Vendor Security Bulletins (e.g., SonicWall, Microsoft).

The case underscores how Ongoing (Beazley Security Labs & Affected Vendors), teams are taking away lessons such as Credential stuffing and weak MFA policies are primary attack vectors for ransomware groups, Zero-day exploits require continuous vulnerability management and proactive mitigations and Infostealers (e.g., Rhadamanthys) fuel credential-based attacks, necessitating monitoring of cybercrime markets, and recommending next steps like Implement comprehensive MFA and conditional access policies for VPNs/remote access, Enforce strong lockout policies and password hygiene to mitigate credential stuffing and Adopt continuous vulnerability management with prioritized patching for critical CVEs, with advisories going out to stakeholders covering Beazley Security Advisories and Vendor Patches/Workarounds (SonicWall, Microsoft, etc.).

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 high confidence (95%), with evidence including credential stuffing to bypass authentication, targeting devices with absent MFA, and compromised VPN Credentials (48%) in attack_vector, Exploit Public-Facing Application (T1190) with high confidence (90%), with evidence including external Service Exploits (23%) in attack_vector, and cVE-2025-* vulnerabilities in SonicWall SSLVPN, SharePoint, CrushFTP, etc., and Valid Accounts: Default Accounts (T1078.001) with moderate to high confidence (70%), supported by evidence indicating weak Access Controls (Absent MFA, Insufficient Lockout Policies) in SonicWall SSLVPN. Under the Credential Access tactic, the analysis identified Brute Force (T1110) with high confidence (95%), with evidence including credential stuffing to exploit weak lockout policies, and rhadamanthys Infostealer commoditizing stolen credentials and Credentials from Password Stores (T1555) with moderate to high confidence (85%), with evidence including infostealers like Rhadamanthys harvesting credentials, and potential PII (via Infostealers) in data_compromised. Under the Defense Evasion tactic, the analysis identified Valid Accounts: Local Accounts (T1078.003) with moderate to high confidence (80%), with evidence including unauthorized access to corporate networks via compromised VPN credentials, and lateral movement into customer environments and Impair Defenses: Disable or Modify Tools (T1562.001) with moderate to high confidence (70%), with evidence including backdoors established (post-exploitation) in initial_access_broker, and delayed patching of zero-day vulnerabilities enabling persistence. Under the Lateral Movement tactic, the analysis identified Remote Services: Remote Desktop Protocol (T1021.001) with moderate to high confidence (85%), with evidence including lateral movement into customer environments via VPN access, and disrupted Business Operations (Ransomware) implying internal spread and Account Discovery: Local Account (T1087.001) with moderate to high confidence (75%), supported by evidence indicating high value targets such as Corporate Data Repositories suggests internal reconnaissance. Under the Impact tactic, the analysis identified Data Encrypted for Impact (T1486) with high confidence (100%), with evidence including data encryption such as Yes (Ransomware), and akira, Qilin, INC Ransomware strains identified and Data Destruction (T1485) with moderate to high confidence (70%), supported by evidence indicating potential operational disruptions and financial fraud risks. Under the Exfiltration tactic, the analysis identified Exfiltration Over Alternative Protocol: Exfiltration Over Unencrypted/Obfuscated Non-C2 Protocol (T1048.003) with high confidence (90%), with evidence including data exfiltration such as Likely (Ransomware Double Extortion), and data sold on dark web such as Stolen Credentials/Potential Ransomware Data Leaks and Automated Exfiltration (T1020) with moderate to high confidence (80%), with evidence including infostealers (e.g., Rhadamanthys) fuel credential-based attacks, and potential PII (via Infostealers) in data_compromised. Under the Persistence tactic, the analysis identified Account Manipulation: Additional Cloud Credentials (T1098.003) with moderate to high confidence (85%), with evidence including backdoors established (post-exploitation) in initial_access_broker, and credential Rotation (for VPNs) as a containment measure and Server Software Component: Web Shell (T1505.003) with moderate to high confidence (70%), with evidence including exploit Public-Facing Application (CVE-2025-* in SharePoint/CrushFTP), and temporary Mitigations for Zero-Days suggesting web shell usage. Under the Reconnaissance tactic, the analysis identified Gather Victim Host Information (T1592) with moderate to high confidence (80%), with evidence including prolonged (Akira Campaign Against SonicWall) reconnaissance_period, and high value targets such as VPN Appliances, Corporate Data Repositories and Search Open Websites/Domains: Social Media (T1593.001) with moderate confidence (60%), supported by evidence indicating monitor dark web for stolen credentials implies prior OSINT gathering. These correlations help security teams understand the attack chain and develop appropriate defensive measures based on the observed tactics and techniques.