How Immutable Backups Stopped an Admin Takeover

Helping a Client Survive a Malicious Admin Account Takeover With Immutable Backups

One of the most dangerous cybersecurity incidents a business can face is a compromised administrator account. Attackers increasingly focus on privileged accounts because they provide direct access to critical systems, cloud services, backups, and sensitive business data. Unlike traditional malware attacks, an administrator account takeover can allow attackers to operate with legitimate permissions, making detection significantly more difficult.

At Epis Technology, we recently assisted a client that experienced a malicious administrator account compromise. What initially appeared to be a routine login anomaly quickly escalated into a serious incident involving unauthorized configuration changes, attempted backup manipulation, and efforts to disrupt business operations.

Fortunately, the client had implemented immutable backup protection, which ultimately became the key factor that prevented a major disaster.

The First Warning Signs

The incident began when unusual administrative activity was detected outside normal business hours.

The client noticed:

• Unexpected configuration changes
• New administrative actions
• Security settings being modified
• Backup policy alterations
• Unrecognized login activity

Initially, it was unclear whether the actions were caused by a legitimate administrator, a misconfiguration, or something more serious.

A deeper investigation quickly revealed that a privileged account had been compromised.

Why Administrator Accounts Are Prime Targets

Modern attackers understand that administrator credentials provide access to the most valuable systems within an organization.

A compromised admin account can often be used to:

• Disable security controls
• Modify backup policies
• Delete recovery points
• Access sensitive files
• Create additional privileged accounts
• Move laterally through the environment

In many ransomware attacks, backup systems are targeted before encryption even begins.

The Immediate Threat

Once access was obtained, the attacker attempted to weaken the organization’s recovery capabilities.

Our investigation identified attempts to:

• Modify backup settings
• Reduce retention policies
• Disable certain monitoring functions
• Alter access permissions
• Remove recovery options

These actions suggested a deliberate effort to eliminate recovery paths before launching additional malicious activity.

Rapid Incident Response

Epis Technology immediately initiated containment procedures.

We:

• Disabled compromised accounts
• Revoked active sessions
• Audited administrative permissions
• Investigated authentication logs
• Verified backup integrity
• Restricted privileged access
• Reviewed system changes

The primary objective was to stop further damage while preserving recovery options.

Why Immutable Backups Made the Difference

The client had previously implemented a backup strategy that included immutable backup protection.

Unlike traditional backups, immutable backups cannot be altered, deleted, or encrypted during a defined retention period, even by privileged users. Learn how immutable snapshots help stop ransomware before damage.

This protection prevented the attacker from:

• Deleting backup repositories
• Modifying recovery points
• Encrypting protected backup data
• Destroying historical recovery records

As a result, the organization maintained access to clean recovery copies despite the administrative compromise.

Recovering the Environment

After containment, Epis Technology performed a complete review of affected systems.

Using protected backup repositories, we were able to:

• Validate clean recovery points
• Restore affected configurations
• Recover altered settings
• Verify system integrity
• Rebuild administrative controls

The recovery process was completed without significant business disruption. Professional recovery services help restore data after severe incidents.

The Synology Role in Recovery

The client’s Synology infrastructure played a critical role in the recovery strategy.

Through properly configured backup and snapshot technologies, the organization benefited from:

• Protected recovery repositories
• Backup monitoring
• Snapshot retention
• Centralized recovery management
• Business continuity protection

These capabilities provided additional layers of resilience during the incident.

Lessons Learned

The incident reinforced several important cybersecurity lessons. Explore cybersecurity strategies to protect against ransomware and evolving threats

Businesses should never assume that privileged accounts are immune from compromise.

Organizations need:

• Multi-factor authentication
• Privileged access management
• Administrative account monitoring
• Immutable backups
• Recovery testing
• Continuous security reviews

Modern attacks increasingly target recovery infrastructure as part of broader attack strategies. Understand why backups are vital to cybersecurity defense

Strengthening Security After Recovery

Following recovery, Epis Technology helped the client further improve their environment by implementing:

• Expanded MFA enforcement
• Conditional access policies
• Administrative account segmentation
• Enhanced monitoring
• Backup validation procedures
• Security auditing workflows

These improvements reduced the likelihood of similar incidents occurring in the future.

Why Immutable Backups Are Becoming Essential

As ransomware groups and cybercriminals become more sophisticated, backup protection must evolve as well.

Immutable backups help protect against:

• Ransomware
• Insider threats
• Administrative mistakes
• Account compromises
• Malicious deletions
• Backup tampering

For many organizations, immutable storage has become a critical component of modern business continuity planning.

About Epis Technology

Epis Technology helps organizations strengthen cybersecurity, protect business data, and improve disaster recovery readiness through secure infrastructure design and proactive backup strategies. The company specializes in Synology consulting, Microsoft 365 and Google Workspace backups, large-scale storage solutions, fully managed PC backups, backup automation, and business continuity planning.  Explore Microsoft 365 backup solutions for secure and reliable data protection

By combining immutable backup technologies, layered security controls, and resilient storage architecture, Epis Technology helps businesses maintain operational continuity and recover quickly from even the most serious security incidents.