Error when importing images

When importing a word document (.doc), I have several of the following error:

2016-02-05 11:32:10,167 http://< the server >/xwiki/bin/view/XWiki/OfficeImporterResults ERROR o.h.u.JDBCExceptionReporter - Batch entry 0 insert into xwikiattachment (XWA_DOC_ID, XWA_FILENAME, XWA_SIZE, XWA_MIMETYPE, XWA_DATE, XWA_AUTHOR, XWA_VERSION, XWA_COMMENT, XWA_ID) values (7042602362081450206, 'image/jpeg;base64,/9j/4AAQSkZJRgABAQ............', 0, NULL, '2016-2-5 11:32:10.000000 +0:0:0', 'xwiki:XWiki.trana', '1.1', '', 1474604203) was aborted. Call getNextException to see the cause.

The xwa_filename field, according to the schema, is "character varying(255)", but the field is too long, because it contains the content of the image, in base64. I don't know why it is in filename field.

I have XWiki Enterprise 7.4, with Postgresql 8.4.18.

Steps to reproduce:
Import the attached todeleteSmallImage.doc, containing only one small PNG image.

However, the image still appear, even if I see lost of exceptions related to this image. That's why this is minor to me.