OctoPrint has an Authentication Bypass via X-Forwarded-For Header when autologinLocal is enabled
Date: 2024-05
Affected: pip/OctoPrint
Attack vector: auth-bypass
Category: vulnerability-disclosure
Severity: High
CVE: CVE-2024-32977
CWE: CWE-290
CVSS: 7.1 (CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:L)

### Impact OctoPrint versions up until and including 1.10.0 contain a vulnerability that allows an unauthenticated attacker to completely bypass the authentication **if the `autologinLocal` option is enabled** within `config.yaml`, even if they come from networks that are not configured as `localNetworks`, by spoofing their IP via the `X-Forwarded-For` header. If autologin is not enabled, this vulnerability does not have any impact. ### Patches The vulnerability has been patched in version 1.10.1. ### Workaround Until the patch has been applied, OctoPrint administrators who have autologin enabled on their instances should disable it and/or to make the instance inaccessible from potentially hostile networks like the internet. ### PoC 1. Enable the `autologinAs` configuration within the `accessControl` section in the [OctoPrint yaml configuration file](https://docs.octoprint.org/en/master/configuration/config_yaml.html#access-control) 2. Set your browser to add the `X-Forwarded-For: 127.0.0.1` header to HTTP requests. For example, this can be done using proxy software like Burp Suite. Alternatively, there are browser extensions such as https://github.com/MisterPhilip/x-forwarded-for, but I haven't tried them. 3. Navigate to OctoPrint and note that it logs you in automatically. ### Credits This vulnerability was discovered and responsibly disclosed to OctoPrint by Jacopo Tediosi.


Mitigations:

Architectural layers (MAESTRO):