CVE-2025-56425

CriticalPublic PoCRCE

Published: 08 January 2026

Published

08 January 2026

Modified

23 January 2026

KEV Added

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Patch

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CVSS Score v3.1 9.1 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H

EPSS Score 0.0064 45.8th percentile

Risk Priority 70 floored blend · peak EPSS

Summary

CVE-2025-56425 is a critical-severity Command Injection (CWE-77) vulnerability in Optimal-Systems Enaio. Its CVSS base score is 9.1 (Critical).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked at the 45.8th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

The strongest mitigations our analysis identified are NIST 800-53 SI-10 (Information Input Validation) and SI-2 (Flaw Remediation).

Deeper analysis

CVE-2025-56425 is a command injection vulnerability (CWE-77) discovered in the AppConnector component of enaio software. It affects AppConnector version 10.10.0.183 and earlier in enaio 10.10, version 11.0.0.183 and earlier in enaio 11.0, and version 11.10.0.183 and earlier in enaio 11.10. The flaw enables authenticated remote attackers to inject arbitrary SMTP commands by supplying crafted input to the /osrest/api/organization/sendmail endpoint. Published on 2026-01-08, it carries a CVSS v3.1 base score of 9.1 (AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H).

Authenticated remote attackers can exploit this vulnerability over the network with low attack complexity and no user interaction. By sending malicious payloads to the specified endpoint, they can inject and execute arbitrary SMTP commands, potentially compromising confidentiality and availability to a high degree as indicated by the CVSS metrics.

Advisories and mitigation details are available in references including the analysis at https://mind-bytes.de/smtp-injection-in-enaio-component-appconnector-cve-2025-56425/ and the vendor site at https://www.optimal-systems.de/enaio. Security practitioners should consult these for patching instructions and workarounds specific to affected enaio deployments.

OWASP Top 10 for Web (2025)

EU & UK References

🇪🇺 ENISA EUVD: EUVD-2026-1505

Vulnerability details

An issue was discovered in the AppConnector component version 10.10.0.183 and earlier of enaio 10.10, in the AppConnector component version 11.0.0.183 and earlier of enaio 11.0, and in the AppConnctor component version 11.10.0.183 and earlier of enaio 11.10. The vulnerability…

allows authenticated remote attackers to inject arbitrary SMTP commands via crafted input to the /osrest/api/organization/sendmail endpoint

CWE(s): CWE-77

Related Threats

MITRE ATT&CK Enterprise TechniquesAI

T1190 Exploit Public-Facing Application Initial Access

Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.

attack.mitre.org →

Why these techniques?

The vulnerability is a command injection in a public-facing REST API endpoint (/osrest/api/organization/sendmail) exploitable remotely over the network (AV:N/AC:L/PR:N), directly enabling T1190: Exploit Public-Facing Application.

Confidence: HIGH · MITRE ATT&CK Enterprise v19.0