CVE-2025-68624

N-able Mail Assure through April 2026 contains a design-level authorization flaw that allows an authenticated SMTP user to send outbound email using MAIL FROM addresses belonging to other tenants. When connecting to the SMTP TCP port and performing SMTP AUTH with valid credentials, the server accepts arbitrary sender domains without enforcing any domain-to-account binding. As a result, an attacker from any tenant can impersonate other tenant domains, producing messages that pass SPF and DMARC validation. NOTE: N-able's position is that the behavior is intended functionality of its shared SMTP relay architecture and that the service does not represent that it enforces per-tenant sender-domain binding.

CVSS v3 4.3 MEDIUM

4.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://deepsec.net/speaker.html#PSLOT782
https://gist.github.com/alessandrobertoldi/1ebe0f48aa0119d787ac0ff710057d92
https://www.n-able.com/products/mail-assure
http://seclists.org/fulldisclosure/2026/Jun/10

Configurations

No configuration.

History

No history.

Information

Published : 2026-09-14 01:16

Updated : 2026-09-14 19:17

NVD link : CVE-2025-68624

Mitre link : CVE-2025-68624

CVE.ORG link : CVE-2025-68624

JSON object : View

Products Affected

No product.

CWE

CWE-290

Authentication Bypass by Spoofing

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