CVE-2025-13079 MEDIUM

CVE-2025-13079: Popup Builder - Create highly converting, mobile friendly marketing popups. <= 4.4.2 - Improper Authorization to Unauthenticated Subscriber Removal via Predictable Tokens

Vendor Popupbuilder
Product Popup Builder – Create highly converting, mobile friendly marketing popups.
Weakness CWE-1241
Published February 19, 2026
Last update April 8, 2026
View on NVD All CVEs

CVSS base score

5.3/10
Attack vector Network
Attack complexity Low
Privileges required None
User interaction None
Confidentiality None
Integrity Low

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

What the vulnerability does

01Description

The Popup Builder – Create highly converting, mobile friendly marketing popups. plugin for WordPress is vulnerable to authorization bypass in all versions up to, and including, 4.4.2. This is due to the plugin generating predictable unsubscribe tokens using deterministic data. This makes it possible for unauthenticated attackers to unsubscribe arbitrary subscribers from mailing lists via brute-forcing the unsubscribe token, granted they know the victim's email address

Explanation of Vulnerability in Simple Terms

02Summary

Popup Builder versions 4.4.2 and earlier contain an integrity vulnerability allowing network-based attackers to modify data without authentication. The attack requires no user interaction and affects the plugin's core functionality. Site administrators should update to a version newer than 4.4.2 to prevent unauthorized modifications.

What an attacker can do

03Attacker Capabilities

Modify plugin data or settings without logging in.

Potential impact on your site

04Site Impact

Attackers can alter popup content, settings, or stored data without your knowledge or permission.

Conditions required to exploit

05Prerequisites

Network access to the site; no authentication or user interaction required.

Key dates

06Disclosure timeline

February 19, 2026 CVE published
April 8, 2026 Record updated