--- title: Content Disarm and Reconstruction (CDR) | klearis description: klearis CDR removes active content from every file and rebuilds it, so email, web, uploads and transfers stay safe without waiting for detection. image: https://klearis.com/hubfs/klearis/n-cdr-b.webp --- [Skip to the main content.](https://klearis.com#main-content) [![klearis-logo-transparent-gray](https://klearis.com/hubfs/klearis-logo-transparent-gray.svg "klearis-logo-transparent-gray")](https://klearis.com) [![klearis-logo-transparent-gray](https://klearis.com/hubfs/klearis-logo-transparent-gray.svg "klearis-logo-transparent-gray")](https://klearis.com) - [Learn CDR](https://klearis.com/learn-about-cdr) - Products - [Web Upload Security](https://klearis.com/web-upload-security) - [File Transfer and Storage](https://klearis.com/file-transfer-storage) - [Email Security](https://klearis.com/email-security) - [Safe File Downloads](https://klearis.com/safe-file-downloads) - [Secure Collaboration](https://klearis.com/secure-collaboration) - [Removable Media Security](https://klearis.com/removable-media-security) - [AI and Data Pipeline Security](https://klearis.com/ai-data-pipeline-security) - [Platform and Integrations](https://klearis.com/platform-and-integrations) - Use Cases - [Defense and Classified Networks](https://klearis.com/cross-domain-file-transfer) - [Education](https://klearis.com/education) - [Financial Services and Insurance](https://klearis.com/secure-document-exchange) - [Healthcare](https://klearis.com/healthcare) - [Legal and Professional Services](https://klearis.com/secure-client-communications) - [Manufacturing and Energy](https://klearis.com/ot-it-boundary-protection) - [Mergers and Acquisitions](https://klearis.com/mergers-and-acquisitions) - [Public Sector](https://klearis.com/public-sector) - [Supply Chain, Retail and Logistics](https://klearis.com/supply-chain-file-security) - [Telecom](https://klearis.com/telecom) - Resources - [Resource Center](https://klearis.com/resource-center) - [Zero Trust](https://klearis.com/zero-trust) - [What CDR does and does not do](https://klearis.com/what-cdr-does-and-does-not-do) - [Blog](https://klearis.com/blog) - Company - [About](https://klearis.com/about) - [Trust Center](https://klearis.com/trust-center) - [Careers](https://klearis.com/career) - [Partners](https://klearis.com/partner-with-us) - [Contact](https://klearis.com/contact-us) [Request a demo](https://klearis.com/contact-us) Toggle Menu Toggle Menu [Request a demo](https://klearis.com/contact-us) - [Learn CDR](https://klearis.com/learn-about-cdr) - Products - [Web Upload Security](https://klearis.com/web-upload-security) - [File Transfer and Storage](https://klearis.com/file-transfer-storage) - [Email Security](https://klearis.com/email-security) - [Safe File Downloads](https://klearis.com/safe-file-downloads) - [Secure Collaboration](https://klearis.com/secure-collaboration) - [Removable Media Security](https://klearis.com/removable-media-security) - [AI and Data Pipeline Security](https://klearis.com/ai-data-pipeline-security) - [Platform and Integrations](https://klearis.com/platform-and-integrations) - Use Cases - [Defense and Classified Networks](https://klearis.com/cross-domain-file-transfer) - [Education](https://klearis.com/education) - [Financial Services and Insurance](https://klearis.com/secure-document-exchange) - [Healthcare](https://klearis.com/healthcare) - [Legal and Professional Services](https://klearis.com/secure-client-communications) - [Manufacturing and Energy](https://klearis.com/ot-it-boundary-protection) - [Mergers and Acquisitions](https://klearis.com/mergers-and-acquisitions) - [Public Sector](https://klearis.com/public-sector) - [Supply Chain, Retail and Logistics](https://klearis.com/supply-chain-file-security) - [Telecom](https://klearis.com/telecom) - Resources - [Resource Center](https://klearis.com/resource-center) - [Zero Trust](https://klearis.com/zero-trust) - [What CDR does and does not do](https://klearis.com/what-cdr-does-and-does-not-do) - [Blog](https://klearis.com/blog) - Company - [About](https://klearis.com/about) - [Trust Center](https://klearis.com/trust-center) - [Careers](https://klearis.com/career) - [Partners](https://klearis.com/partner-with-us) - [Contact](https://klearis.com/contact-us) [Linkedin](https://www.linkedin.com/company/klearis) [X](https://x.com/kleariscdr) By channel [Web Upload Security](https://klearis.com/web-upload-security) [File Transfer and Storage](https://klearis.com/file-transfer-storage) [Email Security](https://klearis.com/email-security) [Safe File Downloads](https://klearis.com/safe-file-downloads) [Secure Collaboration](https://klearis.com/secure-collaboration) [Removable Media Security](https://klearis.com/removable-media-security) [AI and Data Pipeline Security](https://klearis.com/ai-data-pipeline-security) Platform [Platform and IntegrationsWays to connect, deployment and capabilities](https://klearis.com/platform-and-integrations) [Defense and Classified NetworksCross-Domain File Transfer](https://klearis.com/cross-domain-file-transfer) [EducationUniversities, schools and research institutes](https://klearis.com/education) [Financial Services and InsuranceSecure Document Exchange](https://klearis.com/secure-document-exchange) [HealthcareHospitals and clinics](https://klearis.com/healthcare) [Legal and Professional ServicesSecure Client Communications](https://klearis.com/secure-client-communications) [Manufacturing and EnergyOT/IT Boundary Protection](https://klearis.com/ot-it-boundary-protection) [Mergers and AcquisitionsFrom due diligence to integration](https://klearis.com/mergers-and-acquisitions) [Public SectorMinistries, agencies and municipalities](https://klearis.com/public-sector) [Supply Chain, Retail and LogisticsFiles from suppliers and partners](https://klearis.com/supply-chain-file-security) [TelecomMobile, fixed line and broadband providers](https://klearis.com/telecom) Resources [Resource Center](https://klearis.com/resource-center) [Zero Trust](https://klearis.com/zero-trust) [What CDR does and does not do](https://klearis.com/what-cdr-does-and-does-not-do) [Blog](https://klearis.com/blog) Company [About](https://klearis.com/about) [Trust Center](https://klearis.com/trust-center) [Careers](https://klearis.com/career) [Partners](https://klearis.com/partner-with-us) [Contact](https://klearis.com/contact-us) Zero Trust File Security · CDR # Every file sanitized. Nothing left that can run. Every file that enters your organization is rebuilt with Content Disarm and Reconstruction (CDR), in milliseconds. [Request a demo](https://klearis.com/contact-us) [What is CDR](https://klearis.com/learn-about-cdr) How CDR works ## Traditional defenses all try to recognize the threat. Antivirus matches signatures of known malware. Sandboxing watches behavior.Both break against a zero-day, an exploit unknown to the vendor, with no signature and no tell. A simple analogy · Three ways to secure the same gate ![A security gate with a board of known threats; a file that is not on the board walks straight through](https://klearis.com/hubfs/klearis/n-av-a.webp) ANTIVIRUS ### The guard with a wanted poster Matches each face against known criminals. If it matches, stop them. If it doesn't, they walk straight through. PROCESSING~ seconds ![A file watched inside an observation room while other files wait outside](https://klearis.com/hubfs/klearis/n-sb-b.webp) SANDBOX ### The interrogation room Pull the suspect into a sealed room and watch for dangerous behavior before letting them into the terminal. PROCESSING~ minutes ![A file passing through a decontamination chamber and leaving clean](https://klearis.com/hubfs/klearis/n-cdr-b.webp) KLEARIS · CDR ### The decontamination chamber Never checks if anyone is "bad." Everyone gets a clean change of clothes and passes through, every threat left at the door. PROCESSING~ milliseconds [The Gryphon Engine Identify, disarm, rebuild: a deterministic process run on every file. How CDR works →](https://klearis.com/learn-about-cdr) Why klearis ## Protection that does not slow work down. ![](https://klearis.com/hubfs/klearis/icons/shield-check.png) ZERO-DAY Unknown threats removed Active content is removed whether a threat is known or not. ![](https://klearis.com/hubfs/klearis/icons/file-sanitize.png) NO SIGNATURES Prevention without detection Every file is rebuilt, so protection does not depend on recognizing the threat. ![](https://klearis.com/hubfs/klearis/icons/policy-scroll.png) POLICY Configurable per team Policies follow your organization: by user group, by integration, by file format. ![](https://klearis.com/hubfs/klearis/icons/server.png) DEPLOYMENT On-premise and air-gapped Runs on infrastructure you own, with no cloud dependency. ![](https://klearis.com/hubfs/klearis/icons/line-chart.png) SPEED Sub-second processing Files are rebuilt in line, with no quarantine queue to wait on. ![](https://klearis.com/hubfs/klearis/icons/file-doc.png) FIDELITY Files that still work Rebuilt files are visually and functionally identical to the originals. ![](https://klearis.com/hubfs/klearis/icons/api-plug.png) INTEGRATION Connects where files arrive REST API, ICAP, Mail Gateway, Server Agent and more, managed from one Web UI. ![](https://klearis.com/hubfs/klearis/icons/file-scan.png) FILE TYPES Broad file coverage Office, PDF, image, video and audio, archive, text and mail formats, including nested archives. Products ## Deploy once.Protect every path a file can take. [Web Upload Security Files uploaded through portals and web applications, rebuilt before they are stored or processed. Learn more →](https://klearis.com/web-upload-security) [File Transfer and Storage Server Agent sanitizes files in batch and through remote file transfer. Learn more →](https://klearis.com/file-transfer-storage) [Email Security Mail Gateway and Outlook Add-in sanitize attachments and email content before delivery. Learn more →](https://klearis.com/email-security) [Safe File Downloads Browser extension and ICAP sanitize files downloaded through the browser before they reach the user. Learn more →](https://klearis.com/safe-file-downloads) [Secure Collaboration Files shared between teams and partners, rebuilt before anyone opens them. Learn more →](https://klearis.com/secure-collaboration) [Removable Media Security Files from USB drives and other removable media, rebuilt before they enter the network. Learn more →](https://klearis.com/removable-media-security) [AI and Data Pipeline Security Files entering data and AI pipelines, rebuilt before they are processed. Learn more →](https://klearis.com/ai-data-pipeline-security) [Platform and Integrations REST API, Server Agent, Mail Gateway, ICAP, browser extension, Outlook add-in, desktop client and central Web UI. Learn more →](https://klearis.com/platform-and-integrations) Use cases ## Built for the environments where security actually has to hold. [Cross-Domain File Transfer Defense and Classified Networks →](https://klearis.com/cross-domain-file-transfer) [Universities, schools and research institutes Education →](https://klearis.com/education) [Secure Document Exchange Financial Services and Insurance →](https://klearis.com/secure-document-exchange) [Hospitals and clinics Healthcare →](https://klearis.com/healthcare) [Secure Client Communications Legal and Professional Services →](https://klearis.com/secure-client-communications) [OT/IT Boundary Protection Manufacturing and Energy →](https://klearis.com/ot-it-boundary-protection) [From due diligence to integration Mergers and Acquisitions →](https://klearis.com/mergers-and-acquisitions) [Ministries, agencies and municipalities Public Sector →](https://klearis.com/public-sector) [Files from suppliers and partners Supply Chain, Retail and Logistics →](https://klearis.com/supply-chain-file-security) FAQ ## Frequently asked questions [What CDR does and does not do →](https://klearis.com/what-cdr-does-and-does-not-do) ### What is Content Disarm and Reconstruction (CDR)? CDR treats every file as untrusted and rebuilds it from the elements its format allows, so threats are left out whether they are known or new. It is a shift from detection to prevention. ### How is CDR different from antivirus and sandboxing? Antivirus compares files against a database of fingerprints for known malware. Sandboxing detonates the file to watch what it does. Both try to recognize the threat. CDR does not ask whether a file is malicious: it strips non-compliant elements and active content, then rebuilds a clean file. ### Will rebuilt files still work? The rebuilt file is visually and functionally identical to the original. Trusted macros and URLs can be added to a whitelist through policy management, so they are preserved instead of sanitized. ### Which file types does klearis support? Office, PDF, image, video and audio, archive, text and mail formats are covered. Archives and nested archives are sanitized under the same policies. ### Where can klearis be deployed? On-premise, in air-gapped and isolated networks, at the boundary between networks of different classification levels, and for bulk file processing. ### How does klearis connect to the tools we already run? Through the REST API, Server Agent, Mail Gateway, ICAP, browser extension, Outlook add-in, desktop client and the central Web UI. Sanitization and audit logs can be sent to SIEM platforms. Next step ## Let's run it on your files. Process real files, see what gets removed, and verify that document fidelity is preserved. [Request a demo](https://klearis.com/contact-us)[Contact](https://klearis.com/contact-us#reach-us-directly) ![klearis](https://klearis.com/hubfs/klearis-logo-transparent-gray.svg) Open any file without a second thought. Products [Web Upload Security](https://klearis.com/web-upload-security) [File Transfer and Storage](https://klearis.com/file-transfer-storage) [Email Security](https://klearis.com/email-security) [Safe File Downloads](https://klearis.com/safe-file-downloads) [Secure Collaboration](https://klearis.com/secure-collaboration) [Removable Media Security](https://klearis.com/removable-media-security) [AI and Data Pipeline Security](https://klearis.com/ai-data-pipeline-security) [Platform and Integrations](https://klearis.com/platform-and-integrations) Use Cases [Defense and Classified Networks](https://klearis.com/cross-domain-file-transfer) [Education](https://klearis.com/education) [Financial Services and Insurance](https://klearis.com/secure-document-exchange) [Healthcare](https://klearis.com/healthcare) [Legal and Professional Services](https://klearis.com/secure-client-communications) [Manufacturing and Energy](https://klearis.com/ot-it-boundary-protection) [Mergers and Acquisitions](https://klearis.com/mergers-and-acquisitions) [Public Sector](https://klearis.com/public-sector) [Supply Chain, Retail and Logistics](https://klearis.com/supply-chain-file-security) [Telecom](https://klearis.com/telecom) Company [About](https://klearis.com/about) [Trust Center](https://klearis.com/trust-center) [Careers](https://klearis.com/career) [Partners](https://klearis.com/partner-with-us) [Contact](https://klearis.com/contact-us) - [Privacy Policy](https://klearis.com/legal#privacy) - [Terms of Service](https://klearis.com/legal#terms) © 2026 klearis [X](https://x.com/kleariscdr)[Linkedin](https://www.linkedin.com/company/klearis) Return to top ```json { "@context" : "https://schema.org", "@id" : "https://klearis.com/#organization", "@type" : "Organization", "logo" : { "@type" : "ImageObject", "height" : 588, "url" : "https://klearis.com/hubfs/klearis/klearis-logo.png", "width" : 2247 }, "name" : "klearis", "sameAs" : [ "https://www.linkedin.com/company/klearis", "https://x.com/kleariscdr" ], "url" : "https://klearis.com/" } ``` ```json { "@context" : "https://schema.org", "@id" : "https://klearis.com/#website", "@type" : "WebSite", "name" : "klearis", "publisher" : { "@id" : "https://klearis.com/#organization" }, "url" : "https://klearis.com/" } ``` ```json { "@context" : "https://schema.org", "@type" : "FAQPage", "mainEntity" : [ { "@type" : "Question", "acceptedAnswer" : { "@type" : "Answer", "text" : "CDR treats every file as untrusted and rebuilds it from the elements its format allows, so threats are left out whether they are known or new. 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Trusted macros and URLs can be added to a whitelist through policy management, so they are preserved instead of sanitized." }, "name" : "Will rebuilt files still work?" }, { "@type" : "Question", "acceptedAnswer" : { "@type" : "Answer", "text" : "Office, PDF, image, video and audio, archive, text and mail formats are covered. Archives and nested archives are sanitized under the same policies." }, "name" : "Which file types does klearis support?" }, { "@type" : "Question", "acceptedAnswer" : { "@type" : "Answer", "text" : "On-premise, in air-gapped and isolated networks, at the boundary between networks of different classification levels, and for bulk file processing." }, "name" : "Where can klearis be deployed?" }, { "@type" : "Question", "acceptedAnswer" : { "@type" : "Answer", "text" : "Through the REST API, Server Agent, Mail Gateway, ICAP, browser extension, Outlook add-in, desktop client and the central Web UI. Sanitization and audit logs can be sent to SIEM platforms." }, "name" : "How does klearis connect to the tools we already run?" } ] } ```