For many years, email was the primary attack vector for phishing. Most security systems, organizational awareness efforts, and employee training programs were built around this assumption. However, new research by NTrigo’s research team, Team51, points to a fundamental shift that is already underway and expected to intensify significantly throughout 2026: the browser is becoming the central attack vector.
This does not mean that phishing via email or other channels is disappearing, but rather that the battlefield is clearly expanding. The browser, which until recently was a relatively secondary area, is becoming a preferred entry point for attackers.
Why the browser
The browser is the user’s primary working environment. It is used to access organizational systems, cloud services, financial platforms, management systems, and collaboration tools. It stores authentication cookies, access tokens, active sessions, and sensitive permissions.
Unlike email, where users are already conditioned to be suspicious, the browser is perceived as a safe environment. This sense of security creates an ideal opportunity for social engineering based attacks.
The rise of attacks via browser extensions
One of the key findings of the research is the growing use of malicious browser extensions, or extensions that become malicious after an update.
Attackers take advantage of several recurring patterns:
- Extensions that impersonate legitimate tools such as ad blockers, AI tools, productivity utilities, security tools, or developer tools
- Extensions that request unusually broad permissions to access all websites, read content, modify pages, and inject code
- Extensions that begin as legitimate and later introduce malicious components through automatic updates
- Extensions that display fake system alerts, fake login prompts, or misleading security warnings
Through these extensions, attackers can steal credentials, hijack active sessions, intercept sensitive data, redirect users to phishing sites, or perform actions on their behalf.
Interactive attacks through the browser
Researchers at Team51 also identify a rise in interactive attacks that do not rely solely on malicious links.
Common examples include:
- Web pages that display fake error messages and instruct users to run commands or install components
- Pop up windows that appear to be part of legitimate organizational systems
- Websites impersonating real login pages of well known services
- Content that is personalized for the user based on publicly available information collected in advance
In many cases, the user does not realize this is an attack, but rather perceives it as a legitimate action within their normal workflow.
Why this is more dangerous than email
Browser based attacks bypass many traditional security mechanisms:
- No reliance on email filtering
- Much harder to classify as anomalous content
- The user is already operating within what they perceive as a trusted environment
- Direct and immediate access to organizational systems
In addition, the browser serves as a bridge between personal and organizational contexts, further expanding the attack surface.
Research conclusions
Team51 estimates that in 2026 we will see:
- A continued decline in the ratio of email based attacks compared to browser based attacks
- A significant increase in the abuse of browser extensions as an attack vector
- More sophisticated phishing attacks combining artificial intelligence, personalization, and dynamic content within the browser
- Increased use of silent attacks that do not deploy traditional malware but instead exploit the browser and the user
Recommendations for organizations
The shift toward the browser as a primary attack surface requires a fundamental change in approach:
- Security must include the browser itself, not only servers and networks
- Monitoring and control of installed extensions is essential
- Real time detection of abnormal browser activity is required
- Employee training must include phishing scenarios delivered via websites and browser extensions, not only email
