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.
Scoring
- Severity
- MEDIUM
- CVSS base score
- 4.3
- CVSS vector
- CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N
- EPSS probability
- 0.29%
- CWE
- CWE-290
- Published
- 2026-09-14
- Last modified
- 2026-09-17
Affected products
- N-able Mail Assure
Weakness type
Related vulnerabilities
- CVE-2026-25938 — FUXA Unauthenticated Remote Code Execution in Node-RED Integration
- CVE-2026-27478 — Unity Catalog has a JWT Issuer Validation Bypass Allows Complete User Impersonation
- CVE-2026-33654 — Zero-Click Indirect Prompt Injection and Authentication Bypass via Email Polling
- CVE-2026-31889 — Shopware has a potential take over of app credentials
- CVE-2026-33661 — WeChat Pay callback signature verification bypassed when Host header is localhost
- CVE-2026-76423 — Cisco ISE API Authentication Bypass Vulnerability
- CVE-2026-6213 — Remote Spark SparkView RCE
- CVE-2026-54782 — CoreWCF: Authentication bypass in CoreWCF SAML 1.1 / 2.0 token signature validation