LinkSentry

LinkSentry is a browser extension for Chrome and Firefox that automatically protects you from fraud, phishing and tracking while you browse. The extension runs invisibly in the background and intervenes before you can even open a dangerous page.

Over 157,000 known scam sites are blocked, more than 70 IP logger services are detected and 45 dangerous protocols are stopped. All of this happens in real time without you having to do anything.

Whether phishing emails, fake online shops or hidden tracking links: LinkSentry detects the danger and warns you immediately. The extension was built for people who want to feel safe online without having to be an expert.

LinkSentry works with 14 independent protection layers that are all active at the same time. Each layer specializes in a specific type of threat.

The phishing protection checks every URL you visit against four daily updated blocklists. When a known scam site is detected, LinkSentry blocks access at the network level before the page even loads.

The IP Logger Shield detects over 70 tracking services like Grabify or IPLogger and prevents your IP address from being sent to these services.

The typosquatting warning detects domains that look deceptively similar to well known websites. For example paypa1.com instead of paypal.com.

The download protection pauses suspicious files (.exe, .msi, .bat) from unknown sources and shows you a warning.

The browser locker protection prevents scam sites from freezing your browser and scaring you with fake virus warnings.

The fake shop detection analyzes online shops for suspicious signs like freshly registered domains, missing legal information or cryptocurrency as the only payment method.

The link scanner allows you to right click any link and run a security check with seven different tests without opening the link.

The QR code scanner checks uploaded QR code images and shows you where they lead before you scan them with your phone.

Additionally, LinkSentry offers WebRTC protection. Some websites try to read your real IP address via WebRTC, even if you are using a VPN. LinkSentry detects such attempts and blocks the WebRTC request.

The protocol filter monitors 45 potentially dangerous URL protocols. In addition to well known protocols like javascript: and data:, more exotic protocols like ms-msdt: are also blocked, which have been abused for attacks in the past.

All blocklists are updated daily from four independent threat intelligence sources. These include lists of known phishing domains, malware distribution sites and crypto scam portals.

LinkSentry protects you in many everyday situations. When you receive an email with a suspicious link, LinkSentry automatically checks the link before you open it. When shopping online, the fake shop detection warns you about dubious providers who lure you with unrealistically low prices.

When someone sends you a Grabify link via WhatsApp or Discord, LinkSentry blocks the IP logger immediately at the network level. Your IP address is never transmitted to the attacker.

For parents, LinkSentry offers an additional layer of protection. Children and teenagers often click carelessly on links in social media or messenger apps. LinkSentry intercepts dangerous pages before they load.

LinkSentry is also relevant for businesses and freelancers. Phishing attacks on business email addresses are steadily increasing. With LinkSentry in the browser, employees are automatically protected without needing complex IT infrastructure.

Journalists and activists particularly benefit from the IP logger protection and the WebRTC shield, as these groups are frequently targeted by tracking attempts.

Installation takes less than one minute.

For Chrome: Open the Chrome Web Store and search for LinkSentry. Click Add and confirm the permissions. LinkSentry needs access to network requests to block dangerous pages. After installation, the LinkSentry icon appears in your browser bar. A green dot shows you that protection is active.

For Firefox: Open the Firefox Add-ons page and search for LinkSentry. Click Add to Firefox. The permissions are identical to the Chrome version.

After installation, LinkSentry is immediately active. You do not need to configure anything. All 14 protection layers run automatically in the background. If you want to use the link scanner or QR code scanner, simply click the LinkSentry icon or use the right click menu.

LinkSentry is built with TypeScript and uses the Manifest V3 format for browser extensions. The build process runs through Webpack.

For blocking network requests, the declarativeNetRequest API is used. This works directly at the network level and is therefore faster and more resource efficient than traditional JavaScript based blocking.

Payment for the Pro version is handled through ExtensionPay. There is no custom backend server. All security checks run entirely locally in the browser.

The blocklists are sourced from public threat intelligence feeds and updated regularly.

LinkSentry is completely serverless. There is no custom backend server, no database and no cloud connection. All checks take place exclusively in your browser.

The extension uses practically no system resources. By using the declarativeNetRequest API, threats are blocked at the network level. This takes less than one millisecond and does not burden CPU or memory.

The free plan already offers full basic protection with all 14 protection layers. Pro adds unlimited scans, email protection, messenger protection and detailed reports.

LinkSentry is available for both Chrome and Firefox and also works together with VPN services. The built in WebRTC protection additionally prevents suspicious sites from reading your real IP despite using a VPN.

LinkSentry has a minimalist dashboard that shows you an overview of all blocked threats. You can see how many phishing sites, IP loggers and suspicious downloads were intercepted in the current session.

The Pro version additionally offers a weekly protection report via email. You can see which threats were detected and how your protection status has evolved over time. Pro also includes an evidence export: if you become a victim of a fraud attempt, you can export all details (URLs, redirect chains, server location) as a report and use it when filing a complaint.

LinkSentry does not collect any personal data. The extension works 100% locally in your browser. No visited URLs, no IP addresses and no usage data are sent to external servers.

There is no custom server and no database. The developers do not know which pages you visit or which links you check.

The only external communication happens when updating the blocklists. These are sourced from public threat intelligence feeds and contain no user related data.