Local coverage for cybersecurity firms in Miami is thin, so we've expanded to statewide listings in Florida. Showing 4 cybersecurity firms that serve Miami clients.
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Providers are hand-vetted by our editorial team based on verified client history, domain authority, and AI footprint. Rankings within Miami are then ordered by tier, verification status, rating, and review count — never by pay-to-rank.
ReliaQuest is a Tampa cybersecurity technology company founded in 2007 by Brian Murphy, who continues to serve as Founder and CEO. The company's GreyMatter platform supports security operations across complex enterprise technology environments and now incorporates agentic AI for detection, investigation, threat hunting and response. Current capabilities include security telemetry normalization, detection at source, storage or in transit, SOAR and automation, phishing defense, attack-surface and exposure management, dark-web monitoring and AI-driven red-team and attack-path analysis. ReliaQuest states that GreyMatter can contain threats in under five minutes and uses multiple AI models according to task and data requirements. First-party company history traces the business to Murphy's decision to start ReliaQuest in Tampa in 2007. The company expanded internationally over time and had more than 1,000 employees across multiple operating centers by its own published leadership history. Crunchbase independently identifies ReliaQuest LLC as an active cybersecurity company and confirms Murphy as founder. ReliaQuest lists its global corporate headquarters at 1001 Water Street, Suite 1900, Tampa, Florida 33602.
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ThreatLocker is an Orlando-area cybersecurity company founded in 2017 by Danny Jenkins, Sami Jenkins and John Carolan. Danny Jenkins serves as CEO, Sami Jenkins as COO, and Carolan as Chief Quality Assurance and Co-Founder. The company develops a Zero Trust security platform built around a deny-by-default model that blocks applications, scripts and processes unless they are explicitly permitted. Current capabilities include application allowlisting, Ringfencing, privileged access management, endpoint detection and response, managed detection and response, patch management, storage controls, web content control, endpoint firewall, Zero Trust network access and Zero Trust cloud access. ThreatLocker also provides 24/7 support through its Cyber Hero team. First-party company history states that the founders incorporated ThreatLocker and launched its initial allowlisting product in 2017. By 2024, the company reported protecting more than 50,000 organizations, and its workforce had expanded internationally. ThreatLocker serves businesses, managed service providers, government entities and other organizations seeking tighter control over endpoint, network and cloud activity.
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Cipher is a cybersecurity company founded in 2000 by Eduardo Bouças and later integrated into Prosegur's global cybersecurity business. Prosegur's official acquisition records describe Cipher as a provider of managed security services and security consulting with operations in the United States, Brazil and the United Kingdom. Its service model was supported by 24/7 security operations centers and the Cipher Intelligence security research function. Prosegur reached an agreement to acquire a majority stake in Cipher in December 2018 and completed the transaction in 2019. Bouças remained with the organization as a shareholder and global cybersecurity executive following the deal. Prosegur subsequently consolidated its cybersecurity operations under the Cipher brand across several international markets. Services associated with the business include managed security, security monitoring, incident response, consulting, compliance and threat intelligence. Official Prosegur records specifically identify 2000 as Cipher's founding year and Bouças as founder and CEO. The supplied cipher.com URL could not be reliably fetched during this verification, so site_status is not awarded.
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Quadrant Information Security is a Jacksonville-founded cybersecurity operation that is now part of Harbor IT, a national managed IT and cybersecurity provider. Harbor states that Quadrant's existing cybersecurity team continues to deliver managed security, detection, response, threat hunting and risk-reduction services rather than being replaced by Harbor's general IT staff. The structure keeps Quadrant's security operations function separate from Harbor's day-to-day managed IT delivery teams while giving clients access to additional cloud, infrastructure, compliance and application expertise. Independent cybersecurity industry records document Quadrant as founded in 2011 and headquartered in Jacksonville, Florida. Historical services included managed security, enterprise security consulting, managed firewall services and security-event monitoring built around the Sagan platform. Harbor's current integration page states that existing Quadrant clients can continue using the same cybersecurity team and service model without being required to move helpdesk or infrastructure operations to Harbor. The supplied quadrantsec.com domain now redirects to Harbor IT's Quadrant integration page, confirming the business transition.
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Frequently asked
ReliaQuest currently holds the #1 rank on DirJournal's Cybersecurity & Digital Defense listing for Miami, Florida. Rankings are recalculated as providers earn verification, publish pricing tiers, and accumulate reviews. See the ranked grid above for the full top 4.
Most cybersecurity firms publish pricing tiers on their DirJournal profile. Click any provider above to see their tiers, starting rate, and typical engagement size. Where pricing isn't listed, request a quote directly through the provider's contact link.
Providers are hand-vetted by our editorial team, then ranked by verification status, tier, rating, and review count. Only published listings appear. Location matching for the Miami page runs city-first, expanding to statewide (Florida) or nationwide only when local coverage is thin — this is clearly disclosed on the page when it happens.
No. Because we don't yet index enough cybersecurity firms inside Miami specifically, this page falls back to statewide coverage across Florida. Every provider listed serves Miami clients but may be headquartered elsewhere in the state.
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