CVE-2025-12875: mruby Buffer Overflow — Fix

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.

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CVSS v3.1 Score

5.3

MEDIUM

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L

Weakness Type (CWE)

CWE-119 Buffer Overflow

CWE-787 Out-of-bounds Write

Affected Products

Vendor	Product	Versions
mruby	mruby	All

References

Advisories & Patches

https://github.com/makesoftwaresafe/mruby/commit/93619f06dd378db6766666b30c08978311c7ec94 https://github.com/mruby/mruby/issues/6650#issuecomment-3430851605 https://github.com/mruby/mruby/issues/6650#issuecomment-3430851605

Other References

https://github.com/mruby/mruby/ https://github.com/mruby/mruby/issues/6650 https://github.com/mruby/mruby/issues/6650#event-20443453808 https://vuldb.com/?ctiid.331511 https://vuldb.com/?id.331511 https://vuldb.com/?submit.680879 https://github.com/mruby/mruby/issues/6650

Frequently Asked Questions

What is CVE-2025-12875? +

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. It has a CVSS v3.1 base score of 5.3 (MEDIUM).

How severe is CVE-2025-12875? +

CVE-2025-12875 has a CVSS v3.1 score of 5.3 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.

What products are affected by CVE-2025-12875? +

CVE-2025-12875 affects products from mruby, specifically: mruby. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2025-12875? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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