We have an enterprise account, and till iOS 14 there were no issues, but as soon as user update their phones to iOS 15, they are getting this alert.
The Developer of this app needs to update it to work with this version of iOS
Now, this issue is coming only for enterprise apps running on iOS 15. I have done some research and found this article. https://developer.apple.com/documentation/xcode/using-the-latest-code-signature-format.
In here it states that
To check whether an app called MyApp.app has the new signature, you can use the
codesign utility: % codesign -dv /path/to/MyApp.app
Look in the output for a string such as CodeDirectory v=20500. For any value of v less than 20400, you need to re-sign your app.
I did that and my output was indeed v=20400. I have signed the app using Xcode 12.5 running on Mac OS 11.2.3. I don't think Apple documents are correct for this. (I could be wrong)
Can anyone please help and let me know, what exactly we need to do to get this issue fixed?
EDIT: I was able to solve this issue by upgrading OS to Big Sur. Xcode version was 12.5.
I had same issue, use xcode 13.0 to build the ipa. It should work.