Bug in the PDFBox Plugin Causes Blockage during Content Reindexing

Summary

Bug - PDFBOX-2522 in the PDFBox plugin causes blockage during content reindexing. Confluence 5.7.x - 5.8.9, which ships with PDFBox version 1.8.4 is affected by the bug.

Steps to Reproduce

1. Add the problematic .pdf attachment to your Confluence page.
2. Try to manually rebuild the contents index of your Confluence instance.
3. Notice that during content reindexing the following warnings are thrown in the <Confluence-Home>/logs/atlassian-confluence.log file which then blocks the indexing process:

   2015-07-14 16:44:49,004 WARN [scheduler_Worker-9] [bonnie.search.extractor.BaseAttachmentContentExtractor] addFields Error indexing attachment (Attachment: xxx.pdf v.1 (22544563))
   com.atlassian.bonnie.search.extractor.ExtractorException: Error getting content of PDF document
           at com.atlassian.bonnie.search.extractor.PdfContentExtractor.extractText(PdfContentExtractor.java:96)
           at com.atlassian.bonnie.search.extractor.BaseAttachmentContentExtractor.addFields(BaseAttachmentContentExtractor.java:41)
           at com.atlassian.confluence.plugin.descriptor.ExtractorModuleDescriptor$BackwardsCompatibleExtractor.addFields(ExtractorModuleDescriptor.java:40)
           at com.atlassian.confluence.search.lucene.ConfluenceDocumentBuilder.extractWithLuceneExtractors(ConfluenceDocumentBuilder.java:155)
           at com.atlassian.confluence.search.lucene.ConfluenceDocumentBuilder.getDocument(ConfluenceDocumentBuilder.java:102)
           at com.atlassian.confluence.search.lucene.tasks.AddDocumentIndexTask.perform(AddDocumentIndexTask.java:49)
           at com.atlassian.confluence.search.lucene.tasks.UpdateDocumentIndexTask.perform(UpdateDocumentIndexTask.java:43)
           at com.atlassian.confluence.search.lucene.DefaultConfluenceIndexManager$IndexTaskWriter.apply(DefaultConfluenceIndexManager.java:473)
           at com.atlassian.confluence.search.lucene.DefaultConfluenceIndexManager$IndexTaskWriter.apply(DefaultConfluenceIndexManager.java:457)
   ...
   Caused by: java.io.IOException: javax.crypto.IllegalBlockSizeException: Input length must be multiple of 16 when decrypting with padded cipher
           at javax.crypto.CipherInputStream.getMoreData(CipherInputStream.java:115)
           at javax.crypto.CipherInputStream.read(CipherInputStream.java:233)
           at javax.crypto.CipherInputStream.read(CipherInputStream.java:209)
           at org.apache.pdfbox.pdmodel.encryption.SecurityHandler.encryptData(SecurityHandler.java:312)
           at org.apache.pdfbox.pdmodel.encryption.SecurityHandler.decryptStream(SecurityHandler.java:413)
           at org.apache.pdfbox.pdmodel.encryption.SecurityHandler.decrypt(SecurityHandler.java:386)
           at org.apache.pdfbox.pdmodel.encryption.SecurityHandler.decryptObject(SecurityHandler.java:361)
           at org.apache.pdfbox.pdmodel.encryption.SecurityHandler.proceedDecryption(SecurityHandler.java:192)
           at org.apache.pdfbox.pdmodel.encryption.StandardSecurityHandler.decryptDocument(StandardSecurityHandler.java:158)
           at org.apache.pdfbox.pdmodel.PDDocument.openProtection(PDDocument.java:1600)
           at org.apache.pdfbox.pdmodel.PDDocument.decrypt(PDDocument.java:946)
           at com.atlassian.bonnie.search.extractor.PdfContentExtractor.extractText(PdfContentExtractor.java:64)
           ... 42 more
   Caused by: javax.crypto.IllegalBlockSizeException: Input length must be multiple of 16 when decrypting with padded cipher
           at com.sun.crypto.provider.CipherCore.doFinal(CipherCore.java:913)
           at com.sun.crypto.provider.CipherCore.doFinal(CipherCore.java:824)
           at com.sun.crypto.provider.AESCipher.engineDoFinal(AESCipher.java:436)
           at javax.crypto.Cipher.doFinal(Cipher.java:2048)
           at javax.crypto.CipherInputStream.getMoreData(CipherInputStream.java:112)
   

Workaround

1. Disable the indexing of PDF attachments using this guide
   OR
2. Update the PDFBox plugin manually in <Confluence-Installation>/confluence/WEB-INF/lib folder by replacing the original PDFBox plugin with a version 1.8.8 or newer. Download the newer version here.