identifierForVendor Changing on Application Updates

Number:rdar://22677034 Date Originated:09/13/2015
Status:Open Resolved:
Product:iOS Product Version:Various
Classification:Serious Bug Reproducible:Sometimes
On application updates our customers identifierForVendor is changing despite the API contract stating it won't under normal update scenario's. We have tested on multiple versions of iOS and are experiencing the same issue.

We need to continue doing further research but this is happening in all cases we have tested so far.

Steps to Reproduce:
1. Have a version of an application installed.
2. Note identifierForVendor.
3. Install new version of application from vendor.
4. Note identifierForVendor has changed.

Expected Results:
identifierForVendor has NOT changed between application updates.

Actual Results:
identifierForVendor has changed between application updates.

Various Including: iPhone 6 64GB, iPad Air, iPhone 5S

Version & Build:
Various Including: 8.4, 8.2

Additional Notes:
Identifier Pre Update: D7F4E4A5-B53D-4DD3-8E29-23F5B29F94AE
Identifier Post Update: 47587888-D409-4D56-B73C-1C0924FF8965


Apple support has claimed that app store had a bug between May and July inwhich identifierForVendor (IDFV) for apps installed during this critical dates will compute incorrect value of IDFV. So if you have installed during those dates, the identifierForVendor will change the moment you update past July 21 as it will restore the value it once were prior to the critical dates.

Unfortunately, our users are still seeing the bug even after installing another update (second update after July 21), a reason to believe that the bug may still have persisted even as late as September.

I filed another bug to Apple describing this behavior. But it was just marked it as duplicate of another issue with ID: 22584428 and it is already closed. There is no info about this issue and it's not added to openradar.

By epitomebar at Oct. 8, 2015, 9:15 a.m. (reply...)

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