Networking gear in a datacenter
Image Credits:Getty Images

DNSFilter acquires iOS firewall app Guardian to expand its web-based threat detection tech

DNSFilter, a Washington, D.C.-based provider of DNS-based web content filtering and threat protection, has announced it’s acquiring Guardian, a privacy-protecting firewall for iOS. Financial terms of the deal were not disclosed. 

Guardian was founded in 2013 by Will Strafach, a security researcher and former iPhone jailbreaker who in 2017 discovered that AccuWeather was secretly sending precise location data to a third-party company without a user’s permission. The company’s “smart firewall” iPhone app blocks apps from sharing users’ personal information with third-parties, such as IP addresses and location data, by funneling data through an encrypted virtual private network (VPN). The startup, which claims to have so far blocked more than 5 billion data trackers and 1 billion location trackers, recently joined forces with Brave to integrate its firewall and VPN functionality into its eponymous non-tracking browser.

In a statement announcing its acquisition of Guardian, DNSFilter said the startup’s technology, coupled with its DNS layer security, will help to disrupt the secure web gateway market (or SWG), which relies on static signatures and threat feed lists that seldom identify variations or new attack vectors. Guardian will equip DNSFilter with full web addresses and IP addresses, file types, port filtering and VPN capabilities, enabling “filtering of new internet traffic layers for customers beyond DNS.”

DNSFilter co-founder and CEO Ken Carnesi said that while secure web gateways play a “critical role” in modern cybersecurity strategies, combining DNS layer security with a firewall and VPN combo “presents a massive business opportunity and alleviates the pain points customers face with legacy SWG technology.”

Guardian will remain a standalone app, while DNSFilter’s predictive DNS protection will further help Guardian users.

DNSFilter, founded in 2015 to protect users from threats such as cryptojacking and ransomware, currently has more than 15,000 customers, including Nvidia, Lenovo and the LA Metro. Last year, the company secured $30 million in Series A funding from Insight Partners. Guardian is the company’s latest acquisition. In 2018, DNSFilter acquired Web Shrinker, a startup that uses artificial intelligence and machine learning to analyze and identify threats and domains in real time. 

A new ‘smart firewall’ iPhone app promises to put your privacy before profits

Techcrunch event

Disrupt 2026: The tech ecosystem, all in one room

Your next round. Your next hire. Your next breakout opportunity. Find it at TechCrunch Disrupt 2026, where 10,000+ founders, investors, and tech leaders gather for three days of 250+ tactical sessions, powerful introductions, and market-defining innovation. Register now to save up to $400.

Save up to $300 or 30% to TechCrunch Founder Summit

1,000+ founders and investors come together at TechCrunch Founder Summit 2026 for a full day focused on growth, execution, and real-world scaling. Learn from founders and investors who have shaped the industry. Connect with peers navigating similar growth stages. Walk away with tactics you can apply immediately

Offer ends March 13.

San Francisco, CA | October 13-15, 2026

Topics

, , , , , , , , , , , ,
Loading the next article
Error loading the next article