EMAIL SECURITY · SLE + DISARM

Email attachments,
disarmed before they open.

Before mail reaches the inbox — the MARS engine inspects and sanitizes every attachment. From on-premises mail servers (SLE) to Microsoft 365 and Google Workspace (DISARM), protection tuned to your environment.

  • SLE on-prem
  • DISARM cloud
  • Microsoft 365
  • Google Workspace
  • CDR sanitization
Gartner Featured in Gartner Email Security research alongside 40 vendors worldwide
  • TTA GS Grade 1 — independent benchmark
  • 12-second average analysis · CDR 34 ms
  • Up to 912,000 emails/day
  • No changes to existing infrastructure
APPLICATION · 01

When you need it.

Supports both on-premises mail servers and cloud email environments.

Financial institutions

Mandated to strengthen email attachment security under Korean electronic finance supervision regulations and the ISMS-P framework. Deployed at Korea Investment & Securities, Daishin Securities, and DB Insurance.

Government and public sector

Blocks malicious document files arriving over email at ministries and public corporations. Ideal when only the email path needs protection without cross-network integration.

Enterprise and manufacturing

Blocks malicious documents attached to internal employee emails. Closes the supply-chain attack path at the source.

Healthcare and biotech

Email attachment security for patient information and research data. Built for regulated-industry compliance.

Defense and military

Verifies email attachments in classified-information environments. Reference: LIG Nex1.

Legal and consulting

Prevents malware infection from client document receipt. On-premises deployment keeps data inside the organization.

CAPABILITY · 02

Catch attachments sandboxes
structurally can't see.

The MARS engine disassembles the binary structure of non-executable files. While antivirus and sandbox products focus on executables, MARS dissects the structure of document files that arrive over email.

F.01

MARS attachment detection and blocking

An appliance installed in front of the mail server inspects every attachment before it reaches the recipient. Purpose-built for DOCX, XLSX, PDF, and HWP (Hangul Word Processor, Korea's standard document format) non-executable files — disassembles structures that antivirus engines can't see by design.

  • 12-second average analysis — 10–20x faster than sandbox
  • No perceptible mail delay
  • Full coverage of 309+ non-executable formats
F.02

CDR sanitization option

When detection and blocking aren't enough — add CDR sanitization. Suspect attachments are reassembled into a clean document with macros, scripts, and embedded OLE objects removed. Original layout and comments preserved.

  • 34 ms per file
  • 309+ formats supported
  • Original layout preserved
F.03

Malicious URL detection

Detects and blocks malicious links inside email bodies in real time. Time-of-click rescan catches URLs that go malicious after delivery.

  • Real-time URL analysis in email body
  • Time-of-click rescan supported
  • Phishing landing-page block
F.04

ConTI threat intelligence integration

Auto-ingests national CERT feeds and the latest threat patterns. SLE detections feed back into the ConTI engine to keep raising detection accuracy across every customer environment.

  • 50+ new threats learned per day
  • National CERT feed integration
  • Offline signature distribution supported
ARCHITECTURE · 03

Deployment shaped to your environment.

SLE is an appliance that sits in front of the mail server. DISARM connects to your tenant via cloud API. Neither approach changes your existing infrastructure.

External sender → SLE appliance → employee inbox ON-PREM · INLINE
External sender Email + attachment SLE APPLIANCE MARS engine · 12-second analysis Block malicious Quarantine + admin alert Pass clean 12-second average CDR sanitization option 34 ms · layout preserved Employee inbox Clean mail only
  • Block malicious — quarantine
  • Pass clean (12 seconds)
  • CDR sanitization option (34 ms)
SPECIFICATION · 04

Independently verified numbers.

Where competing sandbox-based solutions take roughly 3 minutes per file, SecuLetter SLE processes attachments in 12.027 seconds in head-to-head testing. Featured in Gartner Email Security research alongside 40 vendors worldwide.

Daily throughput (standard)160,000 emails/day
Daily throughput (enterprise)912,000 emails/day
Avg. analysis speed12.027 seconds (TTA GS Grade 1 benchmark · 200,000-file run)
CDR speed (option)34 ms per file
Supported file formats309+ (industry-leading coverage — HWP, PDF, DOCX, XLSX, images, archives)
DeploymentOn-premises appliance · HA active-active
Impact on existing infrastructureNone — inline in front of the mail server. No MX or DNS changes.
Certifications and compliance100% APT detection (Korean cybersecurity agency benchmark) · TTA GS Grade 1 · Common Criteria EAL2 · Korea public-procurement listed · featured in Gartner Email Security research (one of 40 listed vendors)
REFERENCE · 05

Why SLE and DISARM were chosen for the email path.

SLE

LIG Nex1

Replaced an incumbent global email security solution with SecuLetter SLE. The MARS engine's structural analysis surfaced non-executable document threats the previous solution had been missing.

SLE

Korea Investment & Securities

Strengthened the finance-sector autonomous security program and email attachment security. Email security architecture recognized in the ISMS-P audit. Zero email-borne malware incidents since deployment.

DISARM

IMM Investment

Closed the cloud email attachment security gap after migrating to Microsoft 365. Deployed in minutes without MX record changes — protection added on top of the existing M365 tenant.

DISARM

MOA MOA Inc

Defended a global Google Workspace collaboration environment against external attachment threats. Simple API integration delivered complete email security without additional infrastructure cost.

RESOURCES · 06

Audit-ready summaries for your evaluation.

SLE · On-Prem

SLE one-pager

On-premises email security gateway — spec, certifications, references

Download
DISARM · Cloud

DISARM one-pager

Cloud email security — spec, integrations, deployment guide

Download
POC · BENCHMARK READY IN 3 DAYS

Document security.
See it for yourself.

Run a benchmark with your own files and samples. Deploys inline without changes to your existing infrastructure—results report typically within 3 days.

NDA upfront Government procurement approved Deployed across national ministries Common Criteria EAL2 certified