Six Browser Attack Techniques to Watch in 2026

Most serious security incidents now begin inside a web browser, and many never leave it. A new analysis from Push Security, a browser security vendor, maps six techniques that attackers are using to steal credentials, take over live sessions and move through business applications directly from the browser, often without triggering email or endpoint defenses.

The first category is phishing for credentials and sessions. Modern phishing kits do not simply collect a username and password. Reverse-proxy adversary-in-the-middle (AitM) toolkits such as Tycoon2FA, Sneaky2FA and Evilginx relay credentials and session tokens to the attacker in real time, which defeats most forms of multi-factor authentication (MFA). These kits are sold as turnkey Phishing-as-a-Service platforms with anti-bot protection, dynamic lure generation and automated session replay, so there is almost no technical barrier to launching a sophisticated phishing campaign. Push Security's data indicates that roughly one in every two phishing attempts is delivered outside email, for example through messaging apps, social media, SMS, malicious ads or in-app messages. Because 89 percent of phishing domains stay active for fewer than two days, relying on blocklists of known bad sites is not enough.

ClickFix is a copy-and-paste attack that has grown rapidly since late 2024. Attackers show a fake CAPTCHA or verification challenge and instruct the victim to copy and run a command to fix the problem. That command is actually malicious, typically installing remote access tools or infostealer malware. Microsoft's Digital Defense Report identified ClickFix as the most common initial access vector, responsible for 47 percent of observed attacks. In Push Security's detection data, ClickFix became the dominant technique for the first time in Q2 2026, reaching 52 percent of total detections. Four in five ClickFix payloads intercepted by Push are served through search engines via compromised sites, malvertising and SEO poisoning, completely bypassing email security. The method keeps evolving: InstallFix uses fake installer pages for developer tools such as Claude Code and NotebookLM, where the install command has been replaced with a malicious one, and an earlier campaign called LLMShare used shared conversations on AI chatbot platforms to deliver malware through pages hosted on trusted domains. Every variant shares one thing: a malicious copy-and-paste event in the browser.

Rather than stealing credentials during login, authorization phishing targets what happens after a user authenticates. It abuses OAuth, the standard that lets websites and apps grant limited access to each other, including consent prompts, device code flows and token exchanges. Because the attacker never touches the login step, even phishing-resistant passkeys (login keys stored on a device) do not stop it. Consent phishing convinces the victim to authorize a malicious third-party app through an OAuth grant. Device code phishing takes advantage of the RFC 8628 device authorization grant to bypass standard authentication entirely; Push Security now tracks more than 30 distinct kits offering this method. ConsentFix is a hybrid of ClickFix and OAuth abuse that was first observed in Russian APT29 campaigns and has since been commoditized into criminal tooling.

Malicious browser extensions are another way attackers steal data, log keystrokes and intercept credentials and session tokens as they pass through the browser. Many of these extensions did not begin as malware: attackers acquire legitimate extensions and wait until their install counts are high before pushing a malicious update. Push Security's analysis across its customers found that 46.76 percent of extensions have the permission combinations needed for account takeover with no user interaction. AI browser extensions add another layer of risk. The Verizon Data Breach Investigations Report 2026 found that more than 15 percent of corporate users had unauthorized AI browser extensions installed, and Push found an average of 17 unique AI extensions per company, with one team running 163. These create data exfiltration pathways that traditional data loss prevention controls cannot see. Static risk scoring is a poor predictor of supply chain compromise, because every major extension breach in the past 18 months involved extensions that had scored as low risk beforehand. A default-deny approach with allowlisting, plus monitoring for extension changes, is more effective.

Password-based compromise remains one of the leading causes of breaches, even in organisations that use single sign-on (SSO). SSO is not universal: Security Assertion Markup Language (SAML) often costs extra, self-adopted apps frequently are not configured for it, and many apps allow simultaneous login methods. The result is what Push calls ghost logins: backup credentials that sit outside SSO, are invisible to identity provider logs, and remain active unless someone disables them. In the last million logins observed by Push, one in four used a password rather than SSO, two in five were not protected by multi-factor authentication, and one in five relied on a weak, breached or reused password. Cloudflare's 2026 Threat Report found that 63 percent of all human logins involve credentials that have already been compromised elsewhere.

Session hijacking lets attackers bypass authentication entirely. They take a stolen session token, the digital proof that a user has already logged in, and replay it in their own browser. This defeats even phishing-resistant passkeys because the authentication step has already been completed. The most common source of stolen session tokens is infostealer malware, and ClickFix is now the primary delivery mechanism for it. According to the Verizon Data Breach Investigations Report 2025, 46 percent of infostealer infections that lead to corporate breaches start on non-managed devices such as personal machines, developer workstations and contractor laptops where endpoint detection and response (EDR) is not present. Browser sync features create another bridge: a personal account compromise can directly lead to a corporate breach.

All six techniques play out inside the browser, exploiting gaps in traditional tools that operate at the email, network or endpoint layers. That means security teams need visibility and controls at the browser itself. Push Security describes its browser-based threat detection and response platform as designed to detect and block attacks such as AitM phishing, ClickFix and session hijacking in real time, deployed as a lightweight browser extension without requiring a browser migration. The company also says the platform helps security teams gain visibility and control over extensions and AI tool usage, and harden identities by surfacing credential reuse, SSO gaps and shadow IT. A full guide to 2026 browser attack techniques is available from Push Security. For website owners and IT team