Zscaler DLP: Comprehensive Review & Top Alternatives in 2025

Zscaler is a cloud security provider offering Secure Web Gateway (SWG), Cloud Access Security Broker (CASB), Zero Trust Network Access (ZTNA), and Data Loss Prevention (DLP) solutions. Its Zscaler DLP sits within the larger Zscaler Zero Trust Exchange platform, aiming to inspect and control data in transit across web, SaaS, and other cloud channels. By routing traffic through Zscaler’s global cloud, organizations can apply DLP policies without hosting on-prem hardware. This approach provides a scalable, cloud-native alternative to traditional DLP suites heavily reliant on appliances or endpoint agents.

In this article, we’ll explore Zscaler DLP’s capabilities, limitations, real-world feedback, and how it compares to solutions like Nightfall AI, Forcepoint, Symantec DLP, Trellix DLP, and Digital Guardian—plus a 15+ question FAQ at the end.

Key Features of Zscaler DLP (Slimmed Down)

1. Cloud-Native Architecture
   Delivers DLP as a fully managed service from Zscaler’s global data centers, eliminating on-premises hardware and simplifying scaling.
2. Inline Web & SaaS Inspection
   Zscaler’s secure web gateway proxy inspects encrypted traffic for sensitive data, blocking or alerting on policy violations across major SaaS services and websites.
3. Built-In CASB Integration
   Unifies SaaS discovery and data control through Zscaler’s CASB module, enforcing consistent DLP policies from a single console.
4. Customizable Policy Engine
   Administrators can define regex, dictionaries, and compliance rules for PII, PCI, PHI, etc., choosing whether to block, allow, or alert.

Common Limitations of Zscaler DLP

1. Endpoint Coverage Gaps
   Focuses on data in transit via proxy or CASB. No dedicated endpoint agent for offline scenarios or local file transfers.
2. Email DLP Not Fully Native
   Stronger for web/SaaS channels than email. Many customers rely on separate SEG or Proofpoint-like gateways for complete email DLP.
3. Complex Setup
   Routing traffic through the Zscaler cloud (including SSL inspection) can be time-consuming, demanding significant IT expertise.
4. Potential Latency
   Decrypting and re-encrypting traffic in Zscaler’s cloud can add overhead; user experience may vary depending on geography and bandwidth.
5. No Data-at-Rest Scanning
   Emphasizes exfiltration prevention over discovering sensitive data stored on endpoints or servers.
6. Advanced Policy Learning Curve
   Defining custom detection rules can be cumbersome for new admins, requiring a detailed grasp of the Zscaler UI and policy logic.
7. Premium Licensing
   Often sold in advanced Zscaler bundles. Smaller orgs wanting only DLP might find it expensive.
8. Support Quality Variance
   Some users report inconsistent support, especially with complex policy tuning or local data center issues.

Real-World User Feedback

“Zscaler’s web DLP blocks suspicious uploads effectively, but certain specialized apps required us to configure bypass rules.”

“Full SSL inspection introduced latency. After tuning exceptions, performance was acceptable.”

“The policy engine is powerful but can feel overwhelming for new admins.”

Users praise Zscaler’s inline DLP for web and SaaS traffic but note complexities in configuration, UI, and performance considerations.

Top Alternatives to Zscaler DLP

1. Nightfall AI

Nightfall AI is a cloud-native, AI-powered DLP that integrates via API with key SaaS apps, while also monitoring endpoints and AI usage:

• API-First: Scans Slack, Google Drive, GitHub, etc. directly, without forcing all traffic through a proxy.
• GenAI Coverage: Blocks sensitive data exfiltration to AI tools like ChatGPT.
• Minimal Tuning: Advanced ML detectors reduce false positives.

2. Forcepoint DLP

A behavior-centric DLP covering endpoint, web, email, and CASB channels:

• Risk-Adaptive Policies: Enforcement changes based on user risk.
• Challenges: Potentially heavy resource requirements, steeper deployments.

3. Symantec DLP (Broadcom)

A legacy leader with deep content analysis spanning endpoint and network:

• Fingerprinting & EDM: One of the most robust detection engines.
• Challenges: Complex on-prem/hybrid architecture, slower updates post-Broadcom.

4. Trellix DLP (formerly McAfee)

Integrates McAfee’s DLP suite into XDR workflows:

• Endpoint & Network: Broad coverage, ePolicy Orchestrator ties it together.
• Challenges: Dated UI, frequent false positives, integration overhead.

5. Digital Guardian (Fortra)

Endpoint-focused DLP for IP protection:

• Deep Visibility: Logs file movements, USB usage, and screen captures.
• Challenges: Agent is resource-heavy; best suited for large IP-centric orgs.

Why Nightfall AI Stands Out

Nightfall AI offers a modern approach to DLP—particularly for SaaS, endpoint, and GenAI use cases—unlike Zscaler’s inline proxy model. Key advantages:

• AI-Powered Detection: LLM-based detectors yield fewer false positives vs. rules-based systems.
• GenAI Data Protection: Safeguards sensitive content from leaking into ChatGPT.
• API-Driven: Monitors cloud applications directly, reducing latency and avoiding proxy complexities.
• Scalable & Easy: Installs quickly via prebuilt connectors, minimal admin overhead.
• Cost-Effective: Pay for exactly the coverage you need, no bundling with extraneous modules.

Organizations prioritizing cloud-native security beyond a traditional SWG approach may find Nightfall an appealing alternative or complement to Zscaler DLP.

15+ Frequently Asked Questions (FAQs)

1. What is Zscaler DLP?
   Answer:
   A cloud-based DLP within the Zscaler platform, scanning outbound web and SaaS traffic for sensitive data. Policies can block uploads, form entries, or file sharing in real time.
2. Does Zscaler DLP cover endpoints offline?
   Answer:
   No. Zscaler primarily inspects traffic routed through its cloud. Offline or direct-to-internet traffic not passing through the proxy is invisible to Zscaler.
3. How does Zscaler handle email DLP?
   Answer:
   Zscaler can route SMTP traffic, but it’s not a native email DLP. Many customers pair it with dedicated email gateways (e.g., Proofpoint) or use separate modules.
4. Can Zscaler DLP scan data at rest in cloud storage?
   Answer:
   Generally no. It focuses on in-transit data. You need a CASB feature or third-party scanning for data-at-rest discovery.
5. What types of data can Zscaler detect out of the box?
   Answer:
   Prebuilt dictionaries for PCI (credit cards), PHI (health), PII, plus user-defined regex or keyword lists for other sensitive content.
6. Does SSL inspection slow down traffic?
   Answer:
   Potentially, yes. Decrypting and re-encrypting SSL can add overhead. Latency varies based on network paths and how extensively you apply inspection.
7. Is policy creation in Zscaler easy?
   Answer:
   It can be complex. Defining advanced regex or building custom rules often requires experienced admins or professional services.
8. How does Zscaler compare to endpoint DLP?
   Answer:
   Zscaler handles web/SaaS traffic inline. Endpoint DLP monitors local file operations and offline usage. Many enterprises combine both for complete coverage.
9. How does Zscaler manage false positives?
   Answer:
   Admins tune detection rules, whitelisting or refining triggers. Zscaler’s console logs incidents, letting you adjust thresholds or create exceptions.
10. Is Zscaler DLP suitable for small businesses?
    Answer:
    Usually better for mid-to-large enterprises with robust IT. Smaller teams may find it expensive or complex unless they already use Zscaler’s SWG.
11. What licensing model does Zscaler DLP use?
    Answer:
    Often bundled in premium Zscaler packages. Pricing depends on user count and advanced features. Some customers find it costlier if they only need DLP.
12. How does Zscaler DLP handle generative AI (ChatGPT)?
    Answer:
    If traffic to AI sites is routed through the SWG, Zscaler can block or alert on sensitive content. There’s no direct API-level integration with ChatGPT, so it’s limited to inline scanning.
13. Can Zscaler integrate with SIEM/SOAR tools?
    Answer:
    Yes. Logs and incidents can be exported via syslog or API to Splunk, QRadar, Sentinel, or other platforms for correlation and automated response.
14. Is there a risk of users bypassing Zscaler?
    Answer:
    If employees use unmonitored devices or VPNs that skip the proxy, Zscaler DLP won’t see that traffic. Organizations often enforce secure forwarders or device lock-down to reduce bypass risk.
15. Does Zscaler do document fingerprinting or OCR?
    Answer:
    Primarily pattern-based detection. Advanced document fingerprinting or OCR is limited compared to solutions like Symantec or Forcepoint.
16. Who benefits most from Zscaler DLP?
    Answer:
    Enterprises already using the Zscaler cloud for secure web gateway/CASB who want inline data protection across web and SaaS. Great for distributed workforces comfortable with proxy-based security.
17. Can Zscaler quarantine or encrypt files?
    Answer:
    Zscaler typically blocks or logs policy violations. Encryption or quarantine actions are possible with certain integrated workflows, but not as granular as a dedicated endpoint DLP.
18. How does it compare to next-gen DLP like Nightfall AI?
    Answer:
    Zscaler focuses on in-transit web traffic. Nightfall integrates at the SaaS/app level, covers generative AI more extensively, and typically yields fewer false positives with ML detectors. Many organizations weigh the overhead of a proxy approach vs. API-based scanning.

Conclusion

Zscaler DLP offers a cloud-native approach to inline traffic inspection across web and SaaS, removing on-prem hardware and simplifying expansion. Its synergy with Zscaler’s SWG and CASB modules makes it attractive for large, distributed enterprises already invested in Zscaler’s ecosystem. However, the platform’s lack of endpoint coverage, complex initial setup, and reliance on a proxy-based approach can present challenges, especially for organizations seeking all-encompassing DLP (including email scanning, offline usage, or data at rest).

For those needing a broader, AI-driven solution that covers endpoints, generative AI workflows, and diverse SaaS integrations, Nightfall AI stands out with its API-first model and robust ML-based detectors. Ultimately, your choice depends on existing infrastructure, traffic routing preferences, and DLP scope—Zscaler is well-suited for mid-to-large enterprises comfortable with proxy-based security, while solutions like Nightfall cater to modern, cloud-centric and AI-oriented teams.