Why Storage Layer Security Is Critical for MSPs Managing AWS Environments

Executive summary

Managed service providers have always owned availability, performance, and baseline security for customer environments. In AWS, that responsibility is expanding not because MSPs are adding more services, but because risk is increasingly concentrated in storage.

Cloud storage now holds the most sensitive data most organizations have. It is where applications write data, where users upload files, where partners exchange content, and where backups and archives live. At the same time, more cloud incidents are driven by access misuse, unsafe file ingestion, and malware entering environments quietly through storage rather than through endpoints.

The data supports this shift. A meaningful portion of exposed cloud storage contains sensitive or regulated data. Ransomware shows up in roughly 40 to 45 percent of confirmed breaches, and small and mid sized organizations, which make up the core MSP customer base, are hit more often than large enterprises. When something goes wrong in storage, it is rarely minor.

For MSPs managing AWS environments, this creates a hard reality. Storage risk is inherited, often invisible, and difficult to defend after the fact. Native AWS services provide useful signals, but they are not built to deliver complete, consistent, and provable storage layer security at MSP scale.

This article outlines what MSPs are facing, why GuardDuty alone does not fully solve the problem, what multi tenant storage security really requires, how MSPs monetize it, and how to evaluate vendors through an MSP lens.

MSPs inherit storage risk they cannot see

Cloud storage has quietly become the backbone of most AWS environments. Over time, S3 buckets fill up with application data, customer records, analytics outputs, logs, exports, and third party uploads. Unlike compute resources, storage sticks around. And so do mistakes.

Industry research consistently shows that when cloud storage is exposed, it is rarely empty or harmless. Roughly one out of every ten publicly accessible cloud storage locations contains sensitive data, and most of that information is classified as restricted or confidential. In practice, storage misconfigurations tend to expose the data organizations care about most.

This is where the problem starts for MSPs. MSPs usually onboard environments that already contain years of stored data. That data arrived through different ingestion paths, created by different teams, often without consistent controls. Once the MSP takes responsibility for managing AWS, customers still expect visibility into that data even if it existed long before the relationship began.

The challenge is that storage risk does not announce itself. Buckets do not alert when permissions drift. Files do not raise alarms when they sit idle. Malware can land in storage and remain unnoticed until it is later downloaded or processed.

When that happens, the MSP is pulled in immediately and expected to explain what happened and why it was not caught. That creates a visibility gap. Many MSPs cannot confidently answer basic questions across all managed tenants. Which storage resources are exposed. Whether inbound files are scanned. Whether historical data was ever validated. Or whether malware could already be sitting in S3.

That uncertainty turns into operational risk.

Why GuardDuty is not enough

AWS provides strong native security services, and GuardDuty plays an important role in detecting suspicious activity. Malware Protection for S3 improves coverage by scanning newly uploaded objects in selected buckets. These are useful capabilities, and most MSPs rely on them as part of a broader security stack.

The issue is scope. GuardDuty is designed as a detection service, not a complete storage layer security program. That distinction matters for MSPs.

GuardDuty malware scanning focuses on new uploads, requires explicit selection of buckets and prefixes, and operates within documented size and archive limits. That works in tightly controlled environments where storage structures rarely change.

MSP environments are not like that. New buckets appear regularly. Folder structures evolve. Large files, archives, and backups are common. Data often exists long before any protection is enabled.

Over time, coverage drifts unless someone is actively managing it. Partial protection is hard to explain and even harder to defend. When malware is discovered later, customers do not ask which prefixes were protected or whether a file exceeded a size limit. They assume antivirus existed and failed.

Breach data also shows that many damaging incidents involve data theft, extortion, or malicious files that were already present, not just newly uploaded malware. Detection at upload time alone does not cover inherited data or large portions of real world storage workloads.

For MSPs, GuardDuty provides signals. It does not provide consistent coverage, baseline validation, or audit ready evidence across tenants.

Multi tenant architecture requirements

Managing storage security for one AWS account is manageable. Managing it across dozens or hundreds of customer environments is a different problem entirely.

Customers increasingly expect MSPs to operate as trusted operators, not just administrators. Third party involvement in breaches continues to increase, which raises expectations around isolation, accountability, and proof. MSPs fall into that third party category by default.

Storage security therefore has to be built for multi tenant delivery. MSPs need clear separation between customers, role based access for operators, and audit trails for every action taken. They also need automation for onboarding new accounts, applying baseline controls, and maintaining coverage without constant manual work.

Tools that work fine in a single environment often fall apart at MSP scale. Manual onboarding leads to drift. Fragmented reporting makes evidence difficult to produce. Inconsistent controls create uneven protection across customers.

Effective storage layer security for MSPs requires a centralized control plane that manages scanning, reporting, and remediation consistently, while keeping customer data isolated and under customer control.

Economics How MSPs monetize storage security

The business case for storage security is becoming clearer. Most cybersecurity spending now flows through partners, and managed security services continue to grow. Customers want outcomes, not tools.

Storage security fits naturally into that model. Data exposure, malware ingestion, and ransomware incidents create work customers expect MSPs to handle. When storage security is not productized, MSPs absorb the cost through investigations, reporting, remediation, and customer communication, often without being paid for that effort.

When storage security is delivered as a managed capability, the dynamic changes. MSPs can offer clear service tiers, predictable pricing, and defined outcomes. Incident costs drop. Investigations move faster. Customer confidence improves.

The economics matter. Solutions that make comprehensive scanning unpredictable or expensive lead to less coverage and more risk. MSPs benefit from approaches that encourage scanning broadly and fit into managed service pricing models.

Vendor evaluation criteria

When evaluating storage security vendors, MSPs should look past feature lists and focus on operational fit.

The questions that matter are practical. Can the solution scan both new and existing data. Can it handle large files and archives. Does it operate consistently across multiple accounts. Can it produce clear reports without heavy manual work.

It also has to fit MSP workflows. Integration with AWS services, centralized visibility across customers, and predictable pricing all matter.

Vendors that solve narrow problems but introduce operational friction rarely succeed at MSP scale. The right solution reduces uncertainty, simplifies delivery, and allows MSPs to stand behind their controls with confidence.

Closing thought

For MSPs managing AWS environments, storage is no longer just infrastructure. It is where sensitive data lives, where malware enters quietly, and where incidents become visible.

The shift is already underway. Storage layer security is moving from an afterthought to a baseline expectation. MSPs that recognize this early and build consistent, defensible storage security into their services will reduce risk, improve trust, and strengthen their business.

Those that do not will continue answering uncomfortable questions after the fact.

Where Cloud Storage Security fits

Cloud Storage Security helps MSPs turn storage security into something consistent and operational.

Our in tenant antivirus platform runs directly inside customer AWS accounts and is used to scan both newly ingested and existing data, including large files and common archive formats. This gives MSPs broader coverage without relying on fragile event based workflows or manual bucket configuration.

For managed service providers, the result is fewer blind spots, clearer visibility across tenants, and a security baseline that can be maintained as environments change.

Cloud Storage Security is typically deployed alongside native AWS services to extend storage protection where built in detection stops.

Learn more: https://www.cloudstoragesecurity.com/msp

References

1. Verizon
   Data Breach Investigations Report 2024 and 2025
   Covers ransomware prevalence in breaches, higher impact on small and mid sized organizations, and third party involvement trends
   https://www.verizon.com/business/resources/reports/dbir/
2. IBM Security
   Cost of a Data Breach Report 2024 and 2025
   Provides global and United States breach cost figures and analysis of cloud hosted data exposure
   https://www.ibm.com/reports/data-breach
3. Cloud Security Alliance
   Top Threats to Cloud Computing
   Documents common cloud security failure modes including data exposure, insecure interfaces, and malware ingestion through cloud services
   https://cloudsecurityalliance.org/research/top-threats/ 
4. Amazon Web Services
   Shared Responsibility Model
   Defines customer and operator responsibility for securing data and storage services in AWS environments
   https://aws.amazon.com/compliance/shared-responsibility-model/
5. Amazon Web Services
   Amazon GuardDuty Malware Protection for Amazon S3 Documentation
   Describes how native S3 malware scanning works including scope, configuration requirements, and operational limits
   https://docs.aws.amazon.com/guardduty/latest/ug/malware-protection-s3.html 
6. Amazon Web Services
   Amazon GuardDuty Quotas and Limits
   Details object size limits, archive extraction limits, and coverage constraints for malware scanning
   https://docs.aws.amazon.com/guardduty/latest/ug/guardduty-quotas.html 
7. National Institute of Standards and Technology
   NIST Special Publication 800 53 and 800 61
   Guidance on malware protection, continuous monitoring, and incident response expectations
   https://csrc.nist.gov/publications
8. Cybersecurity and Infrastructure Security Agency
   Cloud Security Technical Reference Architecture
   United States government guidance on securing cloud environments including storage services and data ingestion paths
   https://www.cisa.gov/cloud-security 
9. ENISA
   Threat Landscape for Cloud Computing
   European Union analysis of cloud threats including ransomware, malware, and data exposure risks
   https://www.enisa.europa.eu/topics/threat-risk-management/threats-and-trends 
10. AWS Marketplace
    Cloud Storage Security Antivirus for Amazon S3
    Product documentation describing in tenant deployment, scanning of new and existing objects, and large file support
    https://aws.amazon.com/marketplace/