Wagtail has improper permission handling when deleting form submissions
### Impact
A CMS user with limited access to form pages could delete submissions to form pages they don't have access to by crafting a form submission to delete submissions on a page they do have access to for submissions they don't.
The vulnerability is not exploitable by an ordinary site visitor without access to the Wagtail admin.
### Patches
Patched versions have been released as Wagtail 7.0.7 and 7.3.2. The new 7.4 LTS feature release also incorporates this fix.
### Workarounds
No workaround is available.
### Acknowledgements
Wagtail thanks Vishal Shukla @shukla304 for reporting this issue.
### For more information
If there are any questions or comments about this advisory:
* Visit Wagtail's support channels
https://docs.wagtail.org/en/stable/support.html
* Send an email to [security@wagtail.org](mailto:security@wagtail.org) (view the security policy
https://github.com/wagtail/wagtail/security/policy for more information).