Why ransomware attacks succeed even when backups exist

Written by Subramani Raom Senior Manager, Cybersecurity Solutions Strategy at Acronis

Your backup plan probably won’t survive a ransomware attack. Why? Because backups fail during ransomware attacks when attackers deliberately target and destroy backup systems before launching encryption. In modern attacks, backup infrastructure is often exposed, accessible and unprotected, making recovery impossible. What should serve as a recovery mechanism becomes a single point of failure instead.

Platforms like Acronis Cyber Platform address this problem by combining backup with security controls such as immutability, access protection and threat detection.

For years, backups have been positioned as the ultimate fallback in cybersecurity strategy, the guarantee that even if systems are compromised, recovery is still possible. But there is a new, uncomfortable reality: Backups often fail during ransomware attacks not because they don’t exist but because they are exposed, accessible and unprotected.

It’s no secret that the pace and severity of ransomware attacks are continually accelerating. The number of attacks rose 50% last year, according to the Acronis Cyberthreats Report H2 2025. It’s time for IT and security professionals to rethink long-standing assumptions about backup and recovery.

How attackers systematically break backup strategies

Most ransomware attacks follow a predictable sequence:

Initial access → credential theft → lateral movement → backup discovery → backup destruction → ransomware deployment

To stop this chain, organizations need controls at each stage. For example, Acronis integrates endpoint protection, credential monitoring and backup protection in one platform to detect threats before backups are compromised.

Backup systems are rarely isolated. Once attackers gain administrative credentials, they can:

• Enumerate backup servers and storage repositories.
• Access backup consoles via stolen credentials.
• Delete or encrypt backup files and snapshots.
• Disable backup agents and scheduled jobs.
• Modify retention policies to remove recovery points.

Common techniques include:

• Deleting Volume Shadow Copies (VSS) on Windows systems.
• Using legitimate admin tools (living-off-the-land techniques).
• Targeting hypervisor snapshots in virtual environments.
• Exploiting API access to cloud backup storage.

By the time ransomware is executed, it’s too late. Recovery paths are already gone.

The most common backup failures in ransomware incidents

Across incident response investigations, several recurring weaknesses explain why backup and recovery ransomware strategies fail.

No isolation between production and backup

Backup systems often sit in the same domain, use the same credentials and are reachable from compromised hosts. This eliminates any meaningful separation between production and backup systems.

Weak access controls

Shared admin credentials, lack of multifactor authentication (MFA) and overprivileged service accounts give attackers easy entry into backup infrastructure.

No immutability

If backups can be modified or deleted, attackers will remove them. Traditional backups without immutability offer little resistance.

Untested recovery processes

Organizations frequently discover during an incident that backups are incomplete, corrupted or too slow to restore at scale.

Siloed security and backup tools

Backup systems often operate independently of security monitoring, so attacks on backup infrastructure go undetected.

Why immutability is critical for ransomware protection

If backups can be modified or deleted, attackers will remove them. This is why traditional backups fail.

Immutable backups prevent any changes or deletion for a defined period, ensuring a clean recovery point always exists. Acronis Cyber Platform provides immutable storage with enforced retention policies and protection against credential misuse.

Key characteristics of immutable backup include:

• Write-once, read-many (WORM) storage.
• Time-based retention locks.
• Protection against API and credential misuse.
• Enforcement at the storage layer not just software.

Even if attackers gain full administrative access, immutable backups remain intact. This ensures that a clean recovery point always exists, which is essential for business continuity.

However, immutability alone is not enough. It must be combined with access control, monitoring and recovery validation.

5 ways to protect backups from ransomware

For managed service providers (MSPs) and enterprise IT teams managing multiple environments, securing backups requires consistency and standardization.

Key practices include:

1. Enforce identity separation: Use dedicated credentials and MFA

2. Isolate backup environments: Segment networks and limit access

3. Use immutable backups: Prevent deletion or modification

4. Monitor backup activity: Detect abnormal behavior early

5. Test recovery regularly: Ensure backups can be restored

Platforms like Acronis integrate all these capabilities into a single solution, reducing complexity and improving resilience.

What to do if backups are already compromised

When backups are impacted during a ransomware attack, recovery becomes significantly more complex.

Options to rectify the situation include:

• Identifying older untouched backup copies if they exist.
• Leveraging off-site or cloud-based immutable storage.
• Rebuilding systems from clean baselines.
• Using forensic analysis to determine the last known good state.

This highlights a critical point: Recovery is not just about having backups but about having trustworthy backups.

Building a ransomware-resilient backup strategy

The Acronis research is clear: to protect backups from ransomware, organizations need to move beyond traditional backup thinking and adopt a resilience-first approach.

MSPs and organizations looking to ensure backups are protected from ransomware attacks should invest in protection solutions like those in the Acronis Cyber Platform, which include:

Integrating security and backup

Backup systems should not operate in isolation. Detection, protection and recovery must work together.

Automating protection and recovery

Manual processes fail under pressure. Automated backup validation and recovery orchestration reduce risk.

Ensuring end-to-end visibility

Security teams need visibility into backup status, anomalies and potential compromise indicators.

Designing for attack scenarios

Assume attackers will reach backup systems and design controls accordingly.

The shift toward integrated cyber protection

One of the biggest gaps in traditional architectures is fragmentation. Separate tools for endpoint protection, backup and monitoring create blind spots that attackers exploit.

A more effective approach is consolidating these capabilities into a unified platform that can:

• Detect threats before backup compromise occurs.
• Protect backup infrastructure with the same rigor as production systems.
• Ensure recovery points remain intact and verified.
• Provide centralized visibility across environments.

Solutions like the Acronis Cyber Platform are designed around this integrated model, combining backup, cybersecurity and recovery management into a single operational framework. That model reduces complexity while improving resilience.

Backups fail because they are exposed

Backups still play a critical role in ransomware defense but only if they are designed to withstand active attacks.

The key takeaway is simple: Backups fail not because they are missing but because they are exposed.

To ensure recovery in modern threat environments, organizations must rethink backup architecture with security at its core, embracing immutability, isolation, monitoring and integration.

After all, your backup is only as strong as its ability to survive the attack.

Sponsored and written by Acronis.