https://devzone.nordicsemi.com/f/nordic-q-a/79268/ios-dfu-library-4-11-0-make-ios-app-crash-on-ios-15Hi Support-Team, My iOS app crashed when I use IOS-DFU-Library 4.11.0 I attached the Xcode debug info and iPhone Analytics. Thank you very much!en-USTelligent Community 13Mon, 06 Sep 2021 02:41:41 GMThttps://devzone.nordicsemi.com/thread/328074?ContentTypeID=1Mon, 06 Sep 2021 02:41:41 GMT137ad170-7792-4731-bb38-c0d22fbe4515:920c4fd9-d4b0-4aa6-9fa0-4a4809af03f9Michael.meng<p>thanks for your reply!</p> <p>This problem is fine for systems below iOS 15。</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/328006?ContentTypeID=1Fri, 03 Sep 2021 14:53:00 GMT137ad170-7792-4731-bb38-c0d22fbe4515:9c5d1bbd-c17f-4534-909e-57efbfd2b812Aleksander Nowakowski<p>Hello,</p> <p>Every response for a request in Secure DFU consists of &quot;response op code&quot; (always 0x60), &quot;request op code&quot; (op code of the request for which the response was sent) and the response data&nbsp; The above error could only happen if the &quot;request op code&quot; in the response for Select Object request was Calculate Checksum, instead of Select Object. This doesn&#39;t seem right. See here&nbsp;<a href="https://github.com/NordicSemiconductor/IOS-DFU-Library/blob/8f935c6516969a874d8c2c01f4fdc4188c3d9910/iOSDFULibrary/Classes/Implementation/SecureDFU/Characteristics/SecureDFUControlPoint.swift#L633">github.com/.../SecureDFUControlPoint.swift</a></p> <p>However, the lib shouldn&#39;t crash in that case, but nicely print an error. I need to fix it and ensure the response is correct. Thank you for the report!</p><div style="clear:both;"></div>