CVE-2026-75872

Medium

Description

HTML Injection in the public subscription form in maalfer MailerUp before 1.1.3 allows unauthenticated remote attackers to have the application send a message carrying arbitrary HTML, to an attacker-chosen address and from the form owner's configured sending identity, via the first_name field of the subscription request, which is interpolated unescaped into the double opt-in verification email.

SeverityMedium

CVSS6.9

Exploit probability—

ProductMailerUp

PublishedAug 18, 2026

First seenAug 18, 2026

Weakness typeCWE-80CWE-80

How to fix

Update

maalfer MailerUp1.1.3 or later

Patches

github.com/maalfer/mailerup/commit/da4aedc9621911df4ce0cc8f0b321dd6d10f40a5

Vendor advisories

github.com/maalfer/mailerup/releases/tag/v1.1.3

Affected products

Product	Affected versions	Fixed in
maalfer MailerUp	v < 1.1.3	1.1.3

Check your version

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