CVE-2026-13164: Mailerup

High severity, CVSS 8.8. EPSS: 0.7% chance of exploitation in the next 30 days.

Missing Authentication for Critical Function (CWE-306) in the RegisterView (apps/accounts/views.py), exposed at POST /api/auth/register/, in MailerUp <1.0.1 allows a remote, unauthenticated attacker to self-register a working account on instances where registration is intended to be restricted, because the endpoint applies the AllowAny permission with no email verification, CAPTCHA, or administrator approval. Any account created this way can read all email stored by the instance, resulting in full disclosure of stored messages to an arbitrary unauthenticated attacker

Affected products

• Mailerup Mailerup: before 1.0.1 (fixed in 1.0.1)

Published 2026-06-24. Last modified 2026-06-25.