Authenticated arbitrary file upload to /tmp/ and /tmp/upload/

Summary

The <redacted>.exe or <redacted>.exe CGI binary can be used to upload arbitrary files to /tmp/upload/ or /tmp/ respectively as any user, although the user interface for uploading files is only shown to the iocadmin user. This issue affects Iocharger firmware for AC models before version 24120701. Likelihood: Moderate – An attacker will need to have knowledge of this CGI binary, e.g. by finding it in firmware. Furthermore, the attacker will need a (low privilege) account to gain access to the <redacted>.exe or <redacted>.exe CGI binary and upload the file, or convince a user with such access to upload it. Impact: Low – The attacker can upload arbitrary files to /tmp/upload/ or /tmp/. However, the attacker is unable to access or use these files without other vulnerabilities. CVSS clarification. The attack can be executed over any network connection the station is listening to and serves the web interface (AV:N), and there are no additional security measure sin place that need to be circumvented (AC:L), the attack does not rely on preconditions (AT:N). The attack does require authentication, but the level of authentication is irrelevant (PR:L), it does not require user interaction (UI:N). Artitrary files can be uploaded, be these files will not be in a location where they can influence confidentiality or availability and have a minimal impact on device integrity (VC:N/VI:L/VA:N). There is no impact on subsequent systems. (SC:N/SI:N/SA:N). While this device is an EV charger handing significant amounts of power, we do not expect this vulnerability to have a safety impact. The attack can be automated (AU:Y).