libreoffice/ww8fuzzer: Heap-buffer-overflow in rtl_uStringbuffer_insert

Project:
git://anongit.freedesktop.org/libreoffice/core

Detailed report: https://oss-fuzz.com/testcase?key=6235706568474624

Project: libreoffice
Fuzzer: libFuzzer_libreoffice_ww8fuzzer
Fuzz target binary: ww8fuzzer
Job Type: libfuzzer_asan_libreoffice
Platform Id: linux

Crash Type: Heap-buffer-overflow READ 12
Crash Address: 0x61500002a87c
Crash State:
rtl_uStringbuffer_insert
rtl::OUStringBuffer::append
ContentNode::GetExpandedText

Sanitizer: address (ASAN)

Recommended Security Severity: Medium

Regressed: https://oss-fuzz.com/revisions?job=libfuzzer_asan_libreoffice&range=201808130712:201808150419

Reproducer Testcase: https://oss-fuzz.com/download?testcase_id=6235706568474624

Issue filed automatically.

See https://github.com/google/oss-fuzz/blob/master/docs/reproducing.md for more information.

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