Certain private tags can cause a crash in the CEST IO Module. This was observed in the dicom2nrrd conversion in the dcipher/JIP context, reference data is not sharable, but we could track down the problem to
https://phabricator.mitk.org/source/mitk/browse/master/Modules/CEST/src/mitkCustomTagParser.cpp$269
There is a lack of tests for valid input here.
Despite all of the obvious flaws of the parsing code around the highlighted line linked above, the particular reason for the crash is a missing check against npos regarding the results of the find() calls. Even without a more comprehensive fix, the hex number string extraction and conversion to ASCII characters should be enhanced by checking against non-ASCII hex values.
CI
These tests fail after my "improvements":
mitkCESTDICOMReaderServiceTest
mitkCustomTagParserTest