The Hidden Flaw: Why Ransomware Cracks Even Backed-Up Systems

Authored by Subramani Rao, Senior Manager of Cybersecurity Solutions Strategy at Acronis

Chances are, your backup strategy won’t hold up during a ransomware attack. The reason is straightforward: attackers intentionally seek out and destroy backup systems before they begin encrypting data. In today’s threat landscape, backup infrastructure is frequently left exposed, easily reachable, and poorly defended — turning what should be your safety net into a critical vulnerability.

Solutions like the Acronis Cyber Platform tackle this issue head-on by merging backup functionality with robust security measures such as data immutability, access safeguards, and threat detection.

For a long time, backups have been seen as the last line of defense in any cybersecurity plan — the assurance that even if everything else fails, you can still recover. But there’s an uncomfortable truth that many organizations are now facing: backups frequently fail during ransomware incidents not because they’re missing, but because they’re vulnerable, reachable, and unprotected.

It’s widely known that ransomware attacks are growing faster and more severe. According to the Acronis Cyberthreats Report H2 2025, attack volume surged by 50% in the past year. It’s time for IT and security teams to challenge their long-held beliefs about backup and recovery.

How attackers methodically dismantle backup strategies

Most ransomware campaigns follow a well-worn path:

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

To disrupt this chain, organizations must implement controls at every stage. Acronis, for instance, combines endpoint protection, credential monitoring, and backup security within a unified platform to catch threats before backups are put at risk.

Backup systems are seldom isolated from the rest of the network. Once attackers obtain administrative credentials, they can:

• Catalog backup servers and storage repositories.
• Log into backup management consoles using stolen credentials.
• Wipe or encrypt backup files and snapshots.
• Shut down backup agents and cancel scheduled tasks.
• Alter retention policies to erase available recovery points.

Typical attack methods include:

• Removing Volume Shadow Copies (VSS) from Windows machines.
• Leveraging legitimate administrative tools (known as living-off-the-land attacks).
• Going after hypervisor snapshots within virtualized environments.
• Exploiting API connections to cloud-based backup storage.

By the time the ransomware payload is deployed, it’s already too late. Every viable recovery path has been eliminated.

The most frequent backup failures during ransomware incidents

Through numerous incident response investigations, several persistent weaknesses have emerged that explain why backup and recovery plans fall apart under ransomware pressure.

No separation between production and backup environments

Backup systems frequently reside in the same domain, share the same credentials, and can be accessed from compromised machines. This erases any real boundary between production and backup infrastructure.

Inadequate access controls

Shared administrative passwords, missing multifactor authentication (MFA), and overly permissive service accounts provide attackers with a straightforward path into backup systems.

Lack of immutability

If backups can be altered or erased, attackers will take advantage of that. Conventional backups without immutability offer almost no defense.

Recovery processes that have never been tested

Many organizations only discover during a crisis that their backups are incomplete, damaged, or too slow to restore across the entire environment.

Disconnected security and backup tools

Backup systems often run independently from security monitoring, meaning attacks on backup infrastructure go unnoticed until it’s too late.

Why immutability is essential for ransomware defense

If backups can be changed or deleted, attackers will eliminate them. This is precisely where traditional backups fall short.

Immutable backups block any modification or deletion for a set period, guaranteeing that a reliable recovery point is always available. The Acronis Cyber Platform delivers immutable storage with enforced retention policies and safeguards against credential abuse.

Core features of immutable backup include:

• Write-once, read-many (WORM) storage architecture.
• Time-based retention locks that cannot be overridden.
• Defenses against API exploitation and credential misuse.
• Enforcement at the storage layer, not merely at the software level.

Even with full administrative access, attackers cannot tamper with immutable backups. This guarantees a trustworthy recovery point at all times, which is vital for maintaining business operations.

That said, immutability by itself isn’t sufficient. It needs to be paired with strong access controls, continuous monitoring, and regular recovery validation.

5 key steps to safeguard backups from ransomware

For managed service providers (MSPs) and enterprise IT teams overseeing multiple environments, keeping backups secure demands consistency and standardized practices.

Essential measures include:

1. Enforce identity separation: Use dedicated credentials and multifactor authentication

2. Isolate backup environments: Segment networks and restrict access

3. Implement immutable backups: Block deletion or modification

4. Monitor backup activity: Catch unusual behavior before it escalates

5. Test recovery on a regular basis: Confirm that backups can actually be restored

Platforms like Acronis bring all these capabilities together in one solution, lowering complexity and strengthening overall resilience.

What to do when backups have already been compromised

If backups are damaged or destroyed during a ransomware attack, the recovery process becomes far more difficult.

Steps to address the situation include:

• Locating older, untouched backup copies if any are available.
• Turning to off-site or cloud-based immutable storage for recovery.
• Reconstructing systems from known clean baselines.
• Conducting forensic analysis to identify the last known good state.

This underscores an important reality: recovery isn’t just about having backups — it’s about having backups you can trust.

Creating a ransomware-resilient backup strategy

The findings from Acronis research are clear: to shield backups from ransomware, organizations must move past conventional backup thinking and embrace a resilience-first mindset.

MSPs and businesses that want to ensure their backups can withstand ransomware attacks should invest in protection solutions like those offered by the Acronis Cyber Platform, which feature:

Unified security and backup

Backup systems shouldn’t operate in a silo. Threat detection, protection, and recovery must function as a coordinated whole.

Automated protection and recovery

Manual processes break down under pressure. Automated backup validation and recovery

Orchestration helps minimize risk.

Achieving complete visibility

Security teams must be able to monitor backup status, identify anomalies, and spot signs of potential compromise.

Planning for attack scenarios

Design your controls with the assumption that attackers will eventually target backup systems.

The move toward integrated cyber protection

A major weakness in traditional architectures is fragmentation. Using separate tools for endpoint protection, backup, and monitoring creates blind spots that attackers can exploit.

A better strategy is to bring these capabilities together into a unified platform that can:

• Detect threats before they compromise backups.
• Secure backup infrastructure with the same level of rigor as production systems.
• Ensure recovery points stay intact and verified.
• Offer centralized visibility across all environments.

Solutions like the Acronis Cyber Platform are built around this integrated approach, combining backup, cybersecurity, and recovery management into a single operational framework. This approach simplifies operations while strengthening resilience.

Backups fail because they are vulnerable

Backups remain essential for ransomware defense, but only if they are built to withstand active attacks.

The key lesson is straightforward: Backups fail not because they are absent, but because they are exposed.

To guarantee recovery in today’s threat landscape, organizations must rethink backup architecture with security at its foundation, embracing immutability, isolation, monitoring, and integration.

Ultimately, your backup is only as reliable as its ability to survive an attack.

Sponsored and written by Acronis.