libreoffice:sftfuzzer: Heap-buffer-overflow in GetSShort

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

Detailed Report: https://oss-fuzz.com/testcase?key=5113413729255424

Project: libreoffice
Fuzzing Engine: libFuzzer
Fuzz Target: sftfuzzer
Job Type: libfuzzer_asan_libreoffice
Platform Id: linux

Crash Type: Heap-buffer-overflow READ 1
Crash Address: 0x619000011818
Crash State:
GetSShort
ParseCMAP
vcl::AbstractTrueTypeFont::indexGlyphData

Sanitizer: address (ASAN)

Recommended Security Severity: Medium

Regressed: https://oss-fuzz.com/revisions?job=libfuzzer_asan_libreoffice&range=202009140623:202009150600

Reproducer Testcase: https://oss-fuzz.com/download?testcase_id=5113413729255424

Issue filed automatically.

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This bug is subject to a 90 day disclosure deadline. If 90 days elapse
without an upstream patch, then the bug report will automatically
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