The upload.sh suffers from a path traversal which allows to create/overwrite arbitrary files as the Linux user the webserver is running as.
For example if the query string is "file=../../../../../tmp/test123" during the file upload, the respective file will be written to /tmp/test123.
Then we get to line 86 and the path to write the temporary file into is /usr/yi-hack-v4/../../../tmp/test123 for example which results in /tmp/test123 as the file path.
As it seems that the feature to update the binaries at line 76 would also allow for Remote Code Execution, as malicious binaries could be placed in there, I recommend to setup a password during installation either dynamically or chosen by the user.
I have to mention that I don't have a YI-Hack running, hence I just leave this simple PoC here.
echo pwned > pwned
curl -X POST <host>/upload.sh?file=../../../tmp/pwned -d "x=@pwned"
The upload.sh suffers from a path traversal which allows to create/overwrite arbitrary files as the Linux user the webserver is running as.
For example if the query string is "file=../../../../../tmp/test123" during the file upload, the respective file will be written to
/tmp/test123.Then we get to line 86 and the path to write the temporary file into is
/usr/yi-hack-v4/../../../tmp/test123for example which results in/tmp/test123as the file path.https://github.com/TheCrypt0/yi-hack-v4/blob/master/src/www/httpd/cgi-bin/upload.sh#L86
As it seems that the feature to update the binaries at line 76 would also allow for Remote Code Execution, as malicious binaries could be placed in there, I recommend to setup a password during installation either dynamically or chosen by the user.
I have to mention that I don't have a YI-Hack running, hence I just leave this simple PoC here.