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How the CVE Works:
The go-httpbin framework is vulnerable to Cross-Site Scripting (XSS) due to improper handling of user-controlled input in the `Content-Type` header via GET parameters. An attacker can manipulate the `Content-Type` parameter to inject malicious JavaScript code into the response. When a victim visits a crafted URL, the injected script executes in their browser, allowing the attacker to steal sensitive information, such as cookies, session tokens, or personal data. The vulnerability arises because the framework does not validate or sanitize the `Content-Type` header, enabling attackers to set it to `text/html` and embed arbitrary scripts.
DailyCVE Form:
Platform: go-httpbin Version: All versions prior to patch Vulnerability: Cross-Site Scripting (XSS) Severity: Critical Date: 2023-10-XX
What Undercode Say:
Exploitation:
1. Craft Malicious URL:
Example: `/response-headers?Content-Type=text/html&xss=`
This URL sets the `Content-Type` to `text/html` and injects a script.
2. Deliver Payload:
Send the crafted URL to the victim via phishing emails, social engineering, or embedded in malicious websites.
3. Execute Payload:
When the victim visits the URL, the script executes in their browser, potentially stealing cookies or session tokens.
Protection:
1. Input Validation:
Validate and sanitize all user-controlled inputs, especially headers like Content-Type.
2. Content-Type Whitelisting:
Restrict `Content-Type` to safe values (e.g., application/json, text/plain) and reject unsafe ones like text/html.
3. Output Encoding:
Encode all dynamic content in responses to prevent script execution.
4. CSP (Content Security Policy):
Implement a strict CSP to block inline scripts and unauthorized sources.
Example Code Fix:
// Validate Content-Type header
func validateContentType(contentType string) bool {
safeTypes := []string{"application/json", "text/plain"}
for _, safeType := range safeTypes {
if contentType == safeType {
return true
}
}
return false
}
// Apply validation in handler
func handler(w http.ResponseWriter, r http.Request) {
contentType := r.URL.Query().Get("Content-Type")
if !validateContentType(contentType) {
http.Error(w, "Invalid Content-Type", http.StatusBadRequest)
return
}
// Proceed with safe Content-Type
}
Commands:
1. Test for XSS:
Use tools like `Burp Suite` or `OWASP ZAP` to test for XSS vulnerabilities.
2. Scan for Vulnerabilities:
Run a security scan with `gosec` or `staticcheck` to identify unsafe code patterns.
3. Update Dependencies:
Ensure go-httpbin is updated to the latest patched version.
Analytics:
- Impact: High risk of data theft, session hijacking, and phishing.
- Exploitability: Easy, as it requires minimal user interaction.
- Prevalence: Common in web applications with improper input handling.
References:
- OWASP XSS Prevention Cheat Sheet
- CVE Database (CVE-2023-XXXX)
- go-httpbin GitHub Repository
This provides a detailed technical breakdown of the vulnerability, its exploitation, and mitigation strategies.
References:
Reported By: https://github.com/advisories/GHSA-528q-4pgm-wvg2
Extra Source Hub:
Undercode
