The Hidden Risk: Why Malware Scanning Fails Against Ransomware
Date Published
We all run malware scanners. They catch trojans, spyware, and viruses. But ransomware is different. If you rely on malware scanning alone, you’re under-protected.
Ransomware attacks in 2025 are more costly, sophisticated, and more damaging than ever. Relying on malware scanning alone is no longer sufficient. CISOs must pair it with modern ransomware behavior detection to ensure true resilience.
What Makes Ransomware Different?
Malware scanners focus on known malicious code. Ransomware often uses code for malicious purposes, encrypting, deleting, or stealing your data for extortion. The real threat is what it does, not what it is.
Signature-based detection, common in malware scanners, matches files against known patterns or hashes. It’s reactive, only flagging threats that are already cataloged. Modern ransomware often uses polymorphic or encrypted code to evade these checks. According to CrowdStrike’s 2025 Global Threat Report, 79% of detections were malware-free.
Behavior-based detection watches for ransomware-specific actions, like slow file encryption, mass renaming, or randomized file names, and can catch threats even without known signatures.
Bottom line: Malware detection helps block entry. Ransomware encryption detection helps limit the damage. Both are needed together.
2025 Ransomware Reality: Escalating Costs, Complex Attacks
Ransomware isn’t just frequent; it’s expensive.
- In 2024, ransomware payments dropped 35% globally to $813 million, yet average payouts soared to around $2 million The GuardianDeepStrike.
- Some attacks cost organizations much more, estimates put total ransomware-related loss (including downtime, recovery, and reputational damage) at around $5.13 million in 2024, expected to rise to $5.5–6 million in 2025 PurpleSec.
- Recovery costs alone (excluding any ransom payment) dropped to $1.53 million in the latest data, down from $2.73 million in 2024, but that shows resilience improvements, not low-risk Grey Matter.
- Ransomware still accounted for 91% of all incurred cyber-insurance losses in the first half of 2025, Axios.
These numbers show how critical behavior-based detection is, not just to stop the attack, but to limit damage and cost.
Ransomware Infects Backups
Backups feel like a safety net. If production gets hit, you can restore. The problem is, backups themselves can be poisoned.
Ransomware doesn’t have to delete your backups to make them useless. It just has to contaminate them. Many teams assume immutability and isolation are enough. “If attackers can’t reach my backups, they can’t hurt me.” But that misses the point: if you’re backing up corrupted or encrypted data, you’re just preserving the damage.
When you restore from those backups, you don’t recover your business; you extend your downtime. That’s why ransomware scanning of backups, snapshots, and vaults before restore is critical. It ensures your recovery points are clean and usable when you need them most.
The End Result Is The Real Risk
Attackers aren’t satisfied once they’re inside. They care about the outcome: encrypted data, stolen files, business disruption, and extortion leverage.
Some don’t even encrypt; they steal data and threaten to leak it (“double extortion”). If you only scan for malware, you miss these stages. Ransomware scanning focuses on ransomware-specific behavior, like data staging, rapid or slow encryption.
Real Business Impact
A single ransomware incident can devastate an organization. Recent victims have lost millions, faced regulatory penalties, and collapsed after failed recoveries and reputational damage. One German device-insurance firm paid $230,000 to attackers, but the real cost was far greater. They cut staff from 170 to eight, sold their headquarters, and ultimately entered insolvency (Tom’s Hardware)
That’s a dramatic reminder that ransomware isn’t just disruptive; the damage can be severely business impacting and permanent.
CISOs: Critical Action Items for 2025
- Scan data-at-rest, including backups, replicas, and vaults, proactively
- Monitor ransomware behaviors, watch for mass encryption, exfil staging, or slow encryption
- Prove your recovery is clean, build confidence with your board and regulators by certifying your backups are ransomware-free.
- Use both malware + ransomware scanning. Cover the entry points (malware) and the destructive outcome (ransomware encryption).
- Practice recovery and response: Regularly test restoration, incident reporting, and communication workflows to reduce downtime and risk.
Final Thoughts
Malware scanners are critical, but insufficient against today’s ransomware. Ransomware is path-driven and outcome-based. To protect your backups, data, and business continuity, you need behavior-based ransomware detection on top of malware scanning.
Whether you're a CISO, IT lead, or IT resilience advocate, this piece offers strategic insights to rethink your cybersecurity posture. Ready to explore how cyber vaulting can fortify your defense-in-depth strategy—and why it’s emerging as a must-have for ransomware readiness? Let’s dive in.
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Managed Databases (RDS / Azure Managed SQL) Status: Not Supported.Note: Direct integrity scanning inside managed database PaaS services is not currently supported. Table 1: Threat Manifestation & Control Fit Architecture ComponentThe "Native" Failure ModeProtection Available (Elastio)AWS S3 / Azure Blob"Infection by Addition"Ransomware writes new encrypted versions of objects. The bucket grows, and "current" versions are unusable.Real-Time Detection & HuntingScans real-time as objects are created. Automates threat hunts for last known clean versions. Automates restores.EC2 / Azure VMs(Self-Hosted DBs)The "Live Database" AttackAttackers encrypt database files (.mdf, .dbf) while the OS remains up. Standard snapshots capture the encrypted state.Automated Integrity ScansAutomated scans of persistent storage in scale-out clusters. Policies control scan frequency for long-lived workloads.AWS BackupVault PoisoningWe lock a backup that was already compromised (Time-to-detect > Backup Frequency).Scan-on-Create (Vault Gate)Automated scanning of backups (EC2, EBS, AMI, EFS, FSx, S3) as they are created. Integrated with AWS Restore Test and LAG Vaults.Azure BackupReplica CorruptionBackup vaults replicate corrupted recovery points to paired regions.Scan-on-CreateAutomated scanning of Azure VM, Managed Disk, and Blob backups as they are created.Managed DBs(RDS / Azure Managed SQL)Logical CorruptionValid SQL commands drop tables or scramble columns.Not SupportedIn these environments, integrity assurance must be addressed through complementary controls such as transaction log analysis, application-layer validation, and point-in-time recovery testing. Conclusion Adopting this control moves us from a posture of "We assume our immutable backups are valid" to "We have algorithmic proof of which recovery points are clean." In an era of compromised identities, this verification is the requisite check-and-balance for cloud storage. This control removes uncertainty from recovery decisions when time, trust, and data integrity matter most.In cloud-native environments, ransomware resilience is no longer defined by whether data exists, but by whether its integrity can be continuously proven before recovery.In practical terms, any cloud-native ransomware recovery strategy that cannot deterministically identify a last known clean recovery point before restoration should be considered operationally incomplete. This perspective reflects patterns we consistently see in enterprise incident response, including insights shared by Elastio advisors with deep experience leading ransomware investigations and cloud recovery efforts.