$ ./mjs/build/mjs poc.js
ASAN:DEADLYSIGNAL
=================================================================
==61059==ERROR: AddressSanitizer: SEGV on unknown address 0x000000000000 (pc 0x56205ea42cf1 bp 0x00000000007c sp 0x7ffdf0132cb8 T0)
==61059==The signal is caused by a READ memory access.
==61059==Hint: address points to the zero page.
#0 0x56205ea42cf0 in mjs_json_stringify src/mjs_json.c:273
#1 0x56205ea42cf0 in mjs_json_stringify src/mjs_json.c:272
#2 0x56205ea42cf0 in mjs_json_stringify src/mjs_json.c:272
#3 0x56205ea42cf0 in mjs_op_json_stringify src/mjs_json.c:494
#4 0x56205ead6955 in cs_varint_decode src/common/cs_varint.c:65
#5 0x56205eaa1a05 in mjs_strcmp src/mjs_string.c:228
#6 0x60b000000082 (<unknown module>)
AddressSanitizer can not provide additional info.
SUMMARY: AddressSanitizer: SEGV src/mjs_json.c:273 in mjs_json_stringify
mJS revision
Commit: b1b6eac
Build platform
Ubuntu 18.04.5 LTS (Linux 5.4.0-44-generic x86_64)
Build steps
Test case
poc.js
Execution steps & Output
Credits: Found by OWL337 team.