FeaturedAccount abuse
How to prevent free-trial abuse without losing real customers
How to prevent free-trial abuse: what it costs you, the signals that flag a recycled trial, and a playbook to stop it at signup without blocking real users.
ShieldLabs Blog
Detection methodology, anonymity research, and abuse-prevention playbooks for teams that protect their traffic.
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Account and offer abuse in ecommerce: a merchant's playbook
The account and offer abuse an ecommerce store faces, why it is not payment fraud, and how to read the device behind each signup without blocking shoppers.
The 10 best multi-accounting detection tools in 2026
The 10 best multi-accounting detection tools in 2026, how detection works by linking accounts to a shared device and network, and how to choose.
Synthetic identity fraud: what it is and how to detect it
What synthetic identity fraud is, how the fabricated-identity lifecycle works, why it is so hard to detect, and how device signals expose the ring behind it.
Card testing fraud explained: the signals that flag a testing session
Card testing fraud sends a burst of small charges to validate stolen cards. The cards rotate, the session does not, and the device behind it is the tell.
The 8 best fraud detection software in 2026
The 8 best fraud detection software in 2026, what to look for, and how the options differ across device signals, decisioning, and chargeback protection.
IP fraud scores explained: Talos, Scamalytics, and IPQS
What an IP fraud score means, how Talos, Scamalytics, and IPQS calculate it, why yours can be high through no fault of your own, and what a score misses.
How to detect geolocation spoofing and prevent fraud
How to detect geolocation spoofing: how it works, why a single IP check fails, and how layered signals expose the mismatch so your team can prevent fraud.
How to detect anti-fingerprint browsers (2026)
Anti-fingerprint browsers spoof canvas, WebGL, fonts, and TLS to break recognition. How to detect them in 2026: the fingerprinting methods and the tells they leave.
Cookieless device identification: how to recognize a returning device without cookies
What cookieless device identification is, how it recognizes a returning device without a stored cookie, and why it is not the same as cookieless analytics.
Browser spoofing: what it is and how spoofed browsers give themselves away
What browser spoofing is, what attackers fake (user agent, OS, screen, timezone), and how a spoofed browser betrays itself through signals that disagree.
15 best VPN and proxy detection tools for fraud prevention in 2026
Compare the best VPN and proxy detection tools for fraud prevention in 2026: what each detects, residential-proxy coverage, pricing, and how to choose.
How to identify anonymous traffic and visitors
How to identify anonymous traffic and recognize returning visitors hidden behind VPNs, proxies, Tor, Private Relay, and anti-detect browsers.
How to detect Tor traffic without blocking real users
Detecting Tor traffic is easy because exit nodes are public. The hard part is acting on it without blocking real users. How web detection actually works.
Will iCloud Private Relay and Chrome IP Protection break your fraud detection?
What iCloud Private Relay and Chrome IP Protection actually change for fraud detection: what degrades, what survives, and why masking is not evasion.
How to prevent friendly fraud with device evidence
Friendly fraud is when a real customer disputes a purchase they made. How it works, why it is hard to prove, and how device evidence helps you fight it.
What is WebGL fingerprinting? How the GPU gives a device away
WebGL fingerprinting identifies a device by how its GPU renders 3D graphics. How it works, what it reveals, and how it differs from canvas.
What is TLS fingerprinting? How JA3 and JA4 identify a client
TLS fingerprinting identifies the software behind a connection from its TLS handshake. How it works, what JA3 and JA4 are, and what it reveals.
What is font fingerprinting? How your installed fonts identify you
Font fingerprinting identifies a device by which fonts are installed, read from how text renders. How it works, what it reveals, and how stable it is.
What is audio fingerprinting? The browser technique, explained
Audio fingerprinting identifies a device by how it processes a sound signal in the browser. How it works, what it reveals, and how stable it is.
How to prevent multi-accounting and stop fraud
How to prevent multi-accounting: detect one person operating many accounts, why IP-based detection fails, and where detection ends and your decision begins.
Impossible travel detection: reading the device behind the location
Impossible travel detection flags an account logging in from two far-apart places. Why velocity alone over-fires on VPNs, and how the device fixes it.
Account takeover detection for web apps: the signal layer at login
How to detect account takeover at login: the device and network signals that flag a suspicious login, why MFA alone misses them, and where the gap is.
What is WebRTC fingerprinting? How it reveals a real IP behind a VPN
WebRTC fingerprinting uses a browser's real-time connection setup to expose network data, including a local or real IP behind a VPN. How it works.
What IP reputation is, and why an IP score alone won't catch fraud
What IP reputation is, how the 0 to 100 score is built, and why a clean IP score alone will not catch fraud. The lagging, shared, and recycled-IP problem.
JA4 fingerprinting explained: how it improves on JA3, and what it actually identifies
What JA4 fingerprinting is, how it fixes JA3's weakness to TLS randomization, the JA4 string format and JA4+ suite, and what it can and cannot identify.
How to detect VPNs in 2026
How to detect VPNs in 2026: the methods that actually work, why an IP check alone fails, and how masked traffic ties to abuse and risk.
Residential proxy detection: why home IPs are the hardest to catch, and how detection actually works
What a residential proxy is, where the home IPs come from, why IP checks miss them, and how residential proxy detection actually works without relying on the address.
What is device fingerprinting? How it works, signals, and uses
What is device fingerprinting: the signals that make up a device fingerprint, how the recognition works across browsers, web vs mobile, and what teams use it for.
What is browser fingerprinting? Detection methods + countermeasures
Browser fingerprinting identifies a device from 100+ datapoints. Learn how canvas, WebGL, and IP signals work, plus detection methods and countermeasures.
What is canvas fingerprinting? How it works and why it is so stable
Canvas fingerprinting identifies a browser by how it renders a hidden image. How it works, what it reveals, how stable it is, and its role in fraud detection.
How to detect account sharing?
How account sharing detection works: counting the distinct devices behind one login, the signals that reveal it, and how to act without false positives.
10 browser fingerprinting techniques explained
The main browser fingerprinting techniques: canvas, WebGL, audio, fonts, TLS (JA3/JA4), and more, what each one reads and how stable it is.
Proxy detection for fraud prevention: how to identify hidden traffic sources
How proxy detection works for fraud prevention: 13 techniques, why residential proxies are hard to spot, and why an IP check alone is never enough.
How to detect anti-detect browsers in 2026
Anti-detect browsers fake a new device per profile to power multi-accounting. How to detect them: the signals that expose them and why no one check is enough.