CVE-2026-21483 — listmonk Vulnerable to Stored XSS Leading to Admin Account Takeover

Description (CNA)

listmonk is a standalone, self-hosted, newsletter and mailing list manager. Prior to version 6.0.0, lower-privileged user with campaign management permissions can inject malicious JavaScript into campaigns or templates. When a higher-privileged user (Super Admin) views or previews this content, the XSS executes in their browser context, allowing the attacker to perform privileged actions such as creating backdoor admin accounts. The attack can be weaponized via the public archive feature, where victims simply need to visit a link - no preview click required. Version 6.0.0 fixes the issue.

Affected (CNA)

Vendor / product	Versions
knadh / listmonk	affected < 6.0.0

CWE

CWE-79

References

https://github.com/knadh/listmonk/security/advisories/GHSA-jmr4-p576-v565

ADP enrichment

CISA-ADP

No English description supplied.

No references supplied.