Uncaught TypeError Message in Clientless VPN
1795
Created On 05/04/21 16:29 PM - Last Modified 06/25/25 02:37 AM
Symptom
- Receiving the following error message when accessing an app via Clientless VPN:
Uncaught TypeError: "pan_toString" is read-only pan_js_all_182s.js line 4 > eval:294:187 <anonymous>
https://{portal's FQDN/IP}/global-protect/vpn-js/pan_js_all_182s.js line 4 > eval:294 <anonymous>
https://{portal's FQDN/IP}/global-protect/vpn-js/pan_js_all_182s.js line 4 > eval:294 <anonymous>
Environment
- Palo Alto Firewalls
- GlobalProtect
- Clientless VPN Portal
Cause
- This error message is caused when a value is not of the expected type within Javascript. In our case it's because we do not support the new ES6 Javascript code
Resolution
- When using the GlobalProtect Clientless VPN feature, we must ensure that the apps we're hosting are only using the supported technologies which can be found at the following document: Supported Technologies
- In our scenario, we were able to confirm the use of the newer ES6 code by utilizing the Developer Tools within Google Chrome as shown below:
Note: This is a snapshot of the Developers Tool console within Google Chrome
Additional Information
For additional information regarding the GlobalProtect Clientless VPN feature, please refer to the following link: