Description

Identifies Cross-Site Scripting (XSS) vulnerabilities in Go HTML templates where user input is handled unsafely. The security risk occurs when untrusted user content is embedded in HTML templates without proper escaping, allowing potential injection of malicious scripts.

Detection Strategy

• Identifies Go template function calls that handle user content

• Checks if user-controlled input data flows into these template functions

• Reports a vulnerability when user input is passed to templates without proper HTML escaping

• Specifically monitors template operations that could render unescaped HTML content

Vulnerable code example

package main

import (
    "html/template"
    "net/http"
)

func vulnerableHandler(w http.ResponseWriter, r *http.Request) {...

✅ Secure code example

package main

import (
    "html/template"
    "net/http"
)

func safeHandler(w http.ResponseWriter, r *http.Request) {...