Description
A weakness has been identified in mruby 3.4.0. This vulnerability affects the function ary_fill_exec of the file mrbgems/mruby-array-ext/src/array.c. Executing a manipulation of the argument start/length can lead to out-of-bounds write. The attack needs to be launched locally. The exploit has been made available to the public and could be used for attacks. This patch is called 93619f06dd378db6766666b30c08978311c7ec94. It is best practice to apply a patch to resolve this issue.
References (8)
Core 8
Core References
Third Party Advisory, VDB Entry vdb-entry
technical-description
https://vuldb.com/?id.331511
Permissions Required, VDB Entry signature
permissions-required
https://vuldb.com/?ctiid.331511
Third Party Advisory, VDB Entry third-party-advisory
https://vuldb.com/?submit.680879
Issue Tracking issue-tracking
https://github.com/mruby/mruby/issues/6650
Issue Tracking issue-tracking
https://github.com/mruby/mruby/issues/6650#event-20443453808
Patch exploit
issue-tracking
https://github.com/mruby/mruby/issues/6650#issuecomment-3430851605
Patch patch
https://github.com/makesoftwaresafe/mruby/commit/93619f06dd378db6766666b30c08978311c7ec94
Various Sources product
https://github.com/mruby/mruby/
Scores
CVSS v3
5.3
EPSS
0.0002
EPSS Percentile
4.3%
Attack Vector
LOCAL
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L
CISA SSVC
Vulnrichment
Exploitation
poc
Automatable
no
Technical Impact
partial
Details
CWE
CWE-119
CWE-787
Status
published
Products (1)
mruby/mruby
3.4.0
Published
Nov 07, 2025
Tracked Since
Feb 18, 2026