The browser security platform for
fraud and account takeover.Magecart and script attacks.browser fingerprinting.PCI DSS 4.0.1 compliance. fraud and account takeover.

Browser-layer security monitors what executes inside your visitors' browsers after a page loads: third-party scripts, AI agents, bots, outbound data requests, and session behaviour. A WAF inspects traffic at the server boundary and stops there. It cannot see JavaScript running client-side, data leaving the browser via third-party script calls, or AI agents operating inside a real browser session. Those events happen after the server has delivered a clean page. cside covers this gap with 100% session visibility and zero added latency, deployed via a single script tag.

PCI DSS 4.0.1 requirement 6.4.3 mandates that organizations maintain a complete, authorized inventory of all scripts on their payment pages and document each script's purpose and integrity. Requirement 11.6.1 mandates continuous monitoring of payment page HTTP headers and script content for unauthorized changes. Both became mandatory on March 31, 2025. cside satisfies both automatically: it inventories every script in real visitor sessions, generates AI-written justifications per script, monitors headers in real time, and produces audit-ready reports accepted by QSAs. VikingCloud has validated cside for these requirements.

AI agent detection requires browser-layer behavioural analysis. AI agents operate inside real browser environments, rotate residential IPs, solve CAPTCHAs, and generate session patterns that defeat IP-based and signature-based detection. cside identifies them by what executes inside the session: atypical device fingerprints, scripted typing cadence with zero variance, absence of natural mouse movement, autofill injection into payment fields, and behavioural signals inconsistent with human navigation. Detection happens before the server registers a login or transaction event. cside achieves 99.7% device fingerprint accuracy across sessions (platform data, 2024 to 2025) with no SDK changes required.

A Magecart attack is a web skimming attack in which malicious JavaScript is injected into a legitimate third-party script to steal payment card data and PII directly from the browser. The attack runs entirely client-side, after the server delivers a clean page. WAFs, SASTs, and pen tests see none of it. cside monitors every third-party script payload in real visitor sessions, not simulated crawls. When a script changes, cside detects it in under 60 seconds on average (platform data, 2024 to 2025), alerts the team, and logs the full payload for forensic investigation and PCI audit evidence.

Winning a card dispute requires session-level evidence captured at transaction time, not reconstructed after a chargeback is filed. Visa and Mastercard dispute processes increasingly require device fingerprints, browser session timelines, script activity logs, and behavioural signals as proof. cside captures full session context automatically for every transaction. When a dispute is filed, a pre-built evidence package is ready to export in 2 seconds. Merchants using cside for chargeback evidence see an average 40% increase in dispute win rates (platform data, 2024 to 2025). cside integrates directly with Chargebacks911 for end-to-end dispute management.