libxml2:html: Heap-use-after-free in xmlParserPrintFileContextInternal

Project:
https://gitlab.gnome.org/GNOME/libxml2.git

Detailed Report: https://oss-fuzz.com/testcase?key=6147358168711168

Project: libxml2
Fuzzing Engine: afl
Fuzz Target: html
Job Type: afl_asan_libxml2
Platform Id: linux

Crash Type: Heap-use-after-free READ 1
Crash Address: 0x621000008d00
Crash State:
xmlParserPrintFileContextInternal
xmlReportError
__xmlRaiseError

Sanitizer: address (ASAN)

Recommended Security Severity: High

Regressed: https://oss-fuzz.com/revisions?job=afl_asan_libxml2&range=202006240141:202006250141

Reproducer Testcase: https://oss-fuzz.com/download?testcase_id=6147358168711168

Issue filed automatically.

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This bug is subject to a 90 day disclosure deadline. If 90 days elapse
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