CVE-2022-21703: Grafana CSRF Privilege Escalation Flaw

CVE-2022-21703 Overview

CVE-2022-21703 is a Cross-Site Request Forgery (CSRF) vulnerability affecting Grafana, the popular open-source platform for monitoring and observability. This vulnerability allows attackers to elevate their privileges by mounting cross-origin attacks against authenticated high-privilege Grafana users, such as Editors or Admins. An attacker can exploit this vulnerability for privilege escalation by tricking an authenticated user into inviting the attacker as a new user with high privileges.

Critical Impact

Successful exploitation enables attackers to gain elevated privileges within Grafana environments by leveraging CSRF attacks against administrators, potentially compromising monitoring infrastructure and sensitive operational data.

Affected Products

• Grafana (versions prior to 7.5.15 and 8.3.5)
• NetApp E-Series Performance Analyzer
• Fedora 34, 35, and 36

Discovery Timeline

• 2022-02-08 - CVE-2022-21703 published to NVD
• 2024-11-21 - Last updated in NVD database

Technical Details for CVE-2022-21703

Vulnerability Analysis

This CSRF vulnerability (CWE-352) exists due to insufficient validation of cross-origin requests in Grafana's user management functionality. The vulnerability allows unauthenticated attackers to craft malicious requests that, when executed in the context of an authenticated high-privilege user's session, can perform unauthorized actions such as inviting new users with elevated permissions.

The attack is network-accessible and requires no prior privileges on the target system. However, it does require user interaction—specifically, an authenticated Grafana administrator or editor must visit a malicious page or click a crafted link while having an active session.

Root Cause

The root cause of CVE-2022-21703 lies in the lack of proper CSRF token validation in Grafana's API endpoints handling user invitation and privilege assignment operations. Without adequate anti-CSRF protections, the application cannot distinguish between legitimate requests initiated by the user and forged requests from malicious cross-origin sources.

Attack Vector

The attack vector for this vulnerability involves social engineering combined with web-based exploitation. An attacker would typically:

1. Create a malicious web page containing hidden form submissions or JavaScript code targeting Grafana's user management endpoints
2. Entice an authenticated Grafana administrator or editor to visit the malicious page while logged into Grafana
3. The malicious page automatically submits requests to the Grafana instance in the context of the victim's authenticated session
4. These requests invite the attacker's account as a new user with administrator or editor privileges

The attack leverages the browser's automatic inclusion of authentication cookies when making cross-origin requests to the Grafana server, allowing the forged requests to be processed as if they originated from the legitimate user.

Detection Methods for CVE-2022-21703

Indicators of Compromise

• Unexpected new user accounts created with elevated privileges (Admin or Editor roles)
• User invitation logs showing accounts created during suspicious timeframes
• Access logs indicating requests to user management endpoints originating from external referrers
• Audit trail entries showing privilege modifications by users who report no such activity

Detection Strategies

• Monitor Grafana audit logs for unexpected user creation or privilege escalation events
• Implement network-level detection for cross-origin requests to Grafana's administrative API endpoints
• Review web server access logs for unusual referrer headers on sensitive endpoints
• Configure alerting on new administrative user creation events

Monitoring Recommendations

• Enable comprehensive audit logging within Grafana to track all user management operations
• Deploy SentinelOne Singularity to monitor for suspicious process behaviors and network connections on systems hosting Grafana
• Implement SIEM correlation rules to detect anomalous user creation patterns
• Establish baseline metrics for normal administrative activity to identify deviations

How to Mitigate CVE-2022-21703

Immediate Actions Required

• Upgrade Grafana to version 7.5.15 or 8.3.5 or later immediately
• Review Grafana user accounts for any unauthorized privilege escalations
• Audit recent user creation events and validate legitimacy with administrators
• Educate privileged users about the risks of clicking untrusted links while logged into administrative interfaces

Patch Information

Grafana has released patched versions addressing this vulnerability. Users should upgrade to Grafana 7.5.15 for the 7.x branch or 8.3.5 for the 8.x branch. The fix is tracked in GitHub Pull Request #45083. Additional details are available in the GitHub Security Advisory GHSA-cmf4-h3xc-jw8w and the Grafana Security Blog Post.

Fedora users should apply the updated packages available through the Fedora package repositories for Fedora 34, 35, and 36. NetApp users should consult the NetApp Security Advisory for guidance on E-Series Performance Analyzer.

Workarounds

• No official workarounds are available for this vulnerability according to the vendor advisory
• As a defense-in-depth measure, restrict network access to Grafana administrative interfaces to trusted networks only
• Implement browser-based security controls such as Content Security Policy headers where possible
• Consider using web application firewalls to filter suspicious cross-origin requests

# Verify Grafana version after upgrade
grafana-cli --version

# Check for unauthorized users via Grafana API
curl -s -H "Authorization: Bearer <API_TOKEN>" \
  https://your-grafana-instance/api/users | jq '.[] | {login, role}'

# Review recent user creation in Grafana logs
grep -i "user created\|user invited" /var/log/grafana/grafana.log