Cyber Resilience

CVE-2025-12875

Memory Safety in Mruby 3.4.0

Published
07 November 2025
Modified
29 April 2026
Patch / advisory
CVSS Score v4 1.9
Click a component to see what it means
Raw vectorCVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
EPSS Score 0.0016 5th percentile
Risk Priority 15 floored blend · peak EPSS

Summary

CVE-2025-12875 is a low-severity Improper Restriction of Operations within the Bounds of a Memory Buffer (CWE-119) vulnerability in Mruby Mruby. Its CVSS base score is 1.9 (Low).

Operationally, ranked at the 5th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

The strongest mitigations our analysis identified map to SI-10 (Information Input Validation) and SI-16 (Memory Protection) — see the control section below for these in your framework.

EU & UK References

Vulnerability Data

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…

more

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.

CWE(s)

Related Threats

CVEs Like This One

CVE-2025-7207Same product: Mruby Mruby
CVE-2026-1979Same product: Mruby Mruby
CVE-2025-13120Same product: Mruby Mruby
CVE-2026-10114Shared CWE-119, CWE-787
CVE-2023-3138Shared CWE-119, CWE-787
CVE-2023-37282Shared CWE-119, CWE-787
CVE-2026-13592Shared CWE-119, CWE-787
CVE-2026-8973Shared CWE-119, CWE-787
CVE-2023-31247Shared CWE-119, CWE-787
CVE-2025-14333Shared CWE-119, CWE-787

Affected Assets

mruby
mruby
3.4.0

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)
  • SI-10 Information Input Validation
  • SI-16 Memory Protection
  • SI-2 Flaw Remediation
Detect
Catch it (NIST detect / respond)

Harden
Shrink the surface (DISA STIG)

Validate
Prove the fix (OWASP ASVS)
  • V17.3.2

Mitigating Controls (NIST 800-53 r5) AI

prevent

Directly requires validation of start/length arguments in ary_fill_exec to block the out-of-bounds write.

prevent

Enforces memory protection that stops or contains the CWE-787 out-of-bounds write in mruby array handling.

prevent

Mandates timely application of the supplied patch (93619f06) to eliminate the flaw in mruby 3.4.0.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.PS-06 mostly match
prevents

Secure SDLC practices (bounds checking, safe APIs, reviews) directly prevent this class of flaw.

ID.RA-01 partial match
prevents

Vulnerability scanning and code analysis directly surface buffer-boundary flaws.

ID.RA-08 partial match
prevents

Receiving and triaging vulnerability disclosures commonly includes buffer-related reports.

PR.AT-02 partial match
prevents

Developer training on secure coding reduces introduction of memory-buffer errors.

PR.PS-02 partial match
prevents

Patching replaces vulnerable code containing buffer-boundary defects.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

detects

Security testing in development catches out-of-bounds accesses before release, covering most instances of the weakness.

prevents

Secure development lifecycle mandates memory-safety practices that directly prevent buffer-boundary violations.

prevents

Application security requirements can specify memory-safety rules, but do not prescribe implementation details.

prevents

Secure architecture and engineering principles include memory-safe design patterns that mitigate buffer overflows.

prevents

Secure coding standards explicitly forbid unsafe buffer operations, directly eliminating CWE-119.

prevents

Change management can enforce review gates that catch unsafe memory operations before deployment.

References