CVE-2022-32275: Grafana Path Traversal Vulnerability

CVE-2022-32275 Overview

CVE-2022-32275 is a reported path traversal vulnerability in Grafana 8.4.3 that allegedly allows unauthorized reading of arbitrary files through specially crafted URI requests. The vulnerability involves manipulating the dashboard snapshot endpoint using URL-encoded constructor prototype pollution combined with directory traversal sequences. It is important to note that Grafana has disputed this vulnerability, stating that the reported behavior results in a benign error page rather than actual file disclosure.

Critical Impact

If exploitable, this vulnerability could allow unauthenticated remote attackers to read sensitive system files such as /etc/passwd, potentially exposing user credentials and system configuration information.

Affected Products

• Grafana 8.4.3

Discovery Timeline

• 2022-06-06 - CVE-2022-32275 published to NVD
• 2024-11-21 - Last updated in NVD database

Technical Details for CVE-2022-32275

Vulnerability Analysis

This reported vulnerability falls under CWE-22 (Improper Limitation of a Pathname to a Restricted Directory), commonly known as path traversal or directory traversal. The attack vector targets the dashboard snapshot functionality in Grafana's web interface.

The reported exploit attempts to leverage JavaScript prototype pollution techniques ({{constructor.constructor') combined with URL encoding (%7B%7B) and traditional directory traversal sequences (../) to escape the intended web root and access arbitrary files on the server's filesystem. The attack is network-based and requires no authentication or user interaction.

However, Grafana has publicly disputed the validity of this CVE, asserting that the described attack vector does not result in file disclosure but instead returns a standard error page. This disagreement highlights the importance of verifying vulnerability claims and understanding vendor perspectives when assessing security risks.

Root Cause

The reported root cause involves improper input validation in the URL handling for the /dashboard/snapshot/ endpoint. Path traversal vulnerabilities typically occur when user-supplied input containing path navigation characters is not properly sanitized before being used in file system operations.

According to Grafana's response, their input validation and error handling mechanisms prevent the traversal sequences from reaching the file system, instead returning an error response. The GitHub Grafana Issue #50336 and GitHub Grafana Comment on Issue #50341 contain additional discussion of this dispute.

Attack Vector

The alleged attack vector involves sending a crafted HTTP request to the Grafana server targeting the snapshot endpoint. The attacker would:

1. Construct a URL with the /dashboard/snapshot/ base path
2. Inject URL-encoded prototype pollution payload (%7B%7Bconstructor.constructor')
3. Append directory traversal sequences (/../../../../../../..)
4. Specify the target file path (e.g., /etc/passwd)

The attack requires network access to the Grafana instance and does not require authentication. Due to the vendor dispute, organizations should test this behavior in their specific environment to determine actual exploitability.

Detection Methods for CVE-2022-32275

Indicators of Compromise

• HTTP requests to Grafana containing URL-encoded constructor patterns (%7B%7Bconstructor)
• Web server logs showing directory traversal sequences (../) in dashboard snapshot URLs
• Unusual access patterns to the /dashboard/snapshot/ endpoint with malformed parameters
• Error logs indicating path resolution failures with suspicious file paths

Detection Strategies

• Deploy web application firewall (WAF) rules to detect and block path traversal patterns in URLs
• Monitor Grafana access logs for requests containing constructor patterns or multiple ../ sequences
• Implement intrusion detection signatures for path traversal attempts against known Grafana endpoints
• Use log analysis tools to correlate unusual snapshot endpoint access with potential reconnaissance activity

Monitoring Recommendations

• Enable verbose logging on Grafana instances to capture full request URIs
• Set up alerts for HTTP 400/404 responses on snapshot endpoints with anomalous request patterns
• Monitor for increases in error rates that may indicate scanning or exploitation attempts
• Review web server access logs regularly for path traversal indicators

How to Mitigate CVE-2022-32275

Immediate Actions Required

• Verify your Grafana version and determine if the reported behavior is reproducible in your environment
• Review Grafana's official position on this CVE through the Grafana Official Website
• Consider upgrading to the latest Grafana release regardless of this specific CVE's validity
• Implement network segmentation to limit access to Grafana instances from untrusted networks

Patch Information

Grafana has disputed this vulnerability and has not released a specific patch addressing CVE-2022-32275. The vendor maintains that the reported attack vector results in an error page rather than file disclosure. Organizations should review the NetApp Security Advisory NTAP-20220715-0008 for additional context and consider upgrading to the latest Grafana version as a general security best practice.

Workarounds

• Restrict network access to Grafana instances using firewall rules or network ACLs
• Deploy a reverse proxy or WAF in front of Grafana to filter malicious requests
• Implement IP allowlisting to limit access to trusted networks
• Consider running Grafana with minimal filesystem permissions to limit potential exposure

# Example: Configure reverse proxy filtering for path traversal
# Nginx configuration to block directory traversal attempts
location /dashboard/snapshot/ {
    if ($request_uri ~* "\.\.\/") {
        return 403;
    }
    if ($request_uri ~* "constructor") {
        return 403;
    }
    proxy_pass http://grafana_backend;
}