Reflected XSS when renaming a file with a vulnerable name which results in an error

How it was found

Hi,

It looks like Nextcloud team will accept the XSS protected by the CSP. (Report #896511) Here is another XSS.

1. Rename an existing filename to <img src=x onerror=prompt(1)>.jpg.
2. Anyone tries to rename this <img src=x onerror=prompt(1)>.jpg with an invalid filename, like add a "" in it, will trigger the XSS attack.
3. Need bypass the CSP.

Thanks

Impact

Cross-Site Scripting