CVE-2022-21713: Grafana Auth Bypass Vulnerability

CVE-2022-21713 Overview

CVE-2022-21713 is an authorization bypass vulnerability in Grafana, the popular open-source monitoring and observability platform. The vulnerability affects multiple API endpoints that fail to properly validate user authorization, allowing authenticated attackers to access team information they should not be permitted to view. This represents a classic Insecure Direct Object Reference (IDOR) pattern combined with improper access control in the Teams API functionality.

Critical Impact

Authenticated users can enumerate team data, view team member information, and discover the total number of teams in the Grafana instance, potentially exposing sensitive organizational structure and user information.

Affected Products

• Grafana versions 5.0.0-beta1 through affected releases
• NetApp E-Series Performance Analyzer
• Fedora 34, 35, and 36

Discovery Timeline

• 2022-02-08 - CVE-2022-21713 published to NVD
• 2024-11-21 - Last updated in NVD database

Technical Details for CVE-2022-21713

Vulnerability Analysis

This vulnerability stems from improper authorization checks (CWE-863) and Insecure Direct Object Reference (CWE-639) in Grafana's Teams API. The affected endpoints process authenticated requests without verifying whether the requesting user has legitimate access to the requested team resources. An attacker who has any valid authentication to the Grafana instance can exploit these endpoints to access data belonging to teams they are not members of.

The vulnerability affects three distinct API endpoints, each exposing different levels of unauthorized data access:

1. /teams/:teamId - Returns complete team details when queried with a specific team ID, regardless of the user's membership in that team
2. /teams/:search - Exposes the total count of teams in search results, including teams the user cannot access
3. /teams/:teamId/members - When the editors_can_admin flag is enabled, reveals team membership information for arbitrary teams

Root Cause

The root cause is the absence of proper authorization middleware on the Teams API endpoints. While these endpoints require authentication (the user must be logged in), they fail to enforce authorization checks to verify the authenticated user's permission to access the specific team resources being requested. This creates a horizontal privilege escalation scenario where any authenticated user can access data belonging to other teams.

Attack Vector

The attack is network-based and requires only low-privilege authenticated access to the Grafana instance. An attacker can exploit this vulnerability through the following approach:

The attacker first authenticates to Grafana with any valid user account, even one with minimal permissions. They can then systematically query the /teams/:teamId endpoint with incrementing team IDs to enumerate all teams in the system. For each valid team ID discovered, the attacker receives full team details that would normally be restricted. If the editors_can_admin configuration flag is enabled, the attacker can additionally query /teams/:teamId/members to retrieve member lists for each discovered team.

This information disclosure can reveal organizational structure, team compositions, and user identities that could be leveraged for further targeted attacks or social engineering campaigns.

Detection Methods for CVE-2022-21713

Indicators of Compromise

• Unusual patterns of API requests to /api/teams/* endpoints from a single user session
• Sequential or enumeration-style requests to team endpoints with incrementing numeric IDs
• High volume of team API queries from users who are not team administrators
• Access log entries showing successful responses to team endpoints for users not in those teams

Detection Strategies

• Monitor Grafana access logs for anomalous patterns of requests to /teams/:teamId and related endpoints
• Implement rate limiting on team API endpoints to detect and slow enumeration attempts
• Deploy web application firewall (WAF) rules to identify and alert on sequential parameter manipulation patterns
• Review audit logs for users accessing team data outside their normal access scope

Monitoring Recommendations

• Enable verbose logging on Grafana API endpoints to capture full request details
• Configure alerting for unusual spikes in team-related API calls per user session
• Implement baseline monitoring for normal team API access patterns to identify anomalies
• Regularly audit user access patterns against team membership to detect unauthorized access attempts

How to Mitigate CVE-2022-21713

Immediate Actions Required

• Upgrade Grafana to version 7.5.15 or 8.3.5 or later immediately
• Review access logs for evidence of exploitation prior to patching
• Audit team configurations and membership for any unauthorized changes
• Consider temporarily restricting network access to Grafana instances until patching is complete

Patch Information

Grafana has released security patches addressing this vulnerability. Users should upgrade to Grafana 7.5.15 or 8.3.5 or later versions. The fix was implemented in GitHub Pull Request #45083, which adds proper authorization checks to the affected Teams API endpoints. Additional details are available in the Grafana Security Blog Post and the GitHub Security Advisory GHSA-63g3-9jq3-mccv.

Workarounds

• There are no known workarounds for this vulnerability; upgrading is the only remediation
• Restrict network access to Grafana instances to trusted users and networks as an interim measure
• Disable the editors_can_admin flag if not required to reduce the attack surface for the members endpoint
• Implement additional network-level access controls to limit who can reach the Grafana API

# Verify current Grafana version
grafana-server -v

# For systemd-based installations, restart after upgrade
sudo systemctl restart grafana-server

# Check Grafana configuration for editors_can_admin setting
grep -r "editors_can_admin" /etc/grafana/