CVE-2025-63421

High

Published: 12 February 2026

Published

12 February 2026

Modified

15 April 2026

KEV Added

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Patch

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CVSS Score 7.8 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

EPSS Score 0.0003 9.2th percentile

Risk Priority 16 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2025-63421 is a high-severity Code Injection (CWE-94) vulnerability in Neocities (inferred from references). Its CVSS base score is 7.8 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploitation for Privilege Escalation (T1068); ranked at the 9.2th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

The strongest mitigations our analysis identified are NIST 800-53 SI-10 (Information Input Validation) and SI-16 (Memory Protection).

Threat & Defense at a Glance

What attackers do: exploitation maps to Exploitation for Privilege Escalation (T1068). What defenders deploy: see the NIST 800-53 controls recommended below.

Threat & Defense Details

Mitigating Controls (NIST 800-53 r5)AI

SI-2 Flaw Remediation good match

prevent

Timely flaw remediation through vendor patching directly eliminates the code injection vulnerability in comeinst.exe, preventing arbitrary code execution by local low-privilege attackers.

SI-10 Information Input Validation good match

prevent

Information input validation in the affected application prevents code injection (CWE-94) via inputs processed by comeinst.exe.

SI-16 Memory Protection good match

prevent

Memory protection safeguards such as DEP and ASLR prevent unauthorized code execution resulting from exploitation of the code injection vulnerability.

MITRE ATT&CK Enterprise TechniquesAI

T1068 Exploitation for Privilege Escalation Privilege Escalation

Adversaries may exploit software vulnerabilities in an attempt to elevate privileges.

attack.mitre.org →

Why these techniques?

Local code injection (CWE-94) in comeinst.exe enables arbitrary code execution from low privileges, directly facilitating exploitation for privilege escalation with high CIA impact.

Confidence: MEDIUM · MITRE ATT&CK Enterprise v18.1

NVD Description

An issue in filosoft Comerc.32 Commercial Invoicing v.16.0.0.3 allows a local attacker to execute arbitrary code via the comeinst.exe file

Deeper analysisAI

CVE-2025-63421 is a code injection vulnerability (CWE-94) in filosoft Comerc.32 Commercial Invoicing version 16.0.0.3. The issue allows a local attacker to execute arbitrary code via the comeinst.exe file. Published on 2026-02-12, it carries a CVSS v3.1 base score of 7.8 (AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H), reflecting high severity due to its potential for significant impact.

A local attacker with low privileges can exploit the vulnerability with low attack complexity and no user interaction. Exploitation through comeinst.exe enables arbitrary code execution, granting high-impact access to confidentiality, integrity, and availability of the affected system.

Mitigation details can be found in advisories referenced at https://ghostline.neocities.org/CVE-2025-63421/ and the vendor site https://www.filosoft.pt. No specific patch or workaround information is provided in the CVE description.