Description
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 products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| knadh | listmonk | < 6.0.0 | — |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Leap 16.0 | govulncheck-vulndb | 0.0.20260723T184607-160000.1.1 | openSUSE-SU-2026:21483-1 |
| openSUSE Leap 15.6 | govulncheck-vulndb | 0.0.20260114T191543-150000.1.137.1 | SUSE-SU-2026:0142-1 |
Affected packages
| Ecosystem | Package | Affected | Fixed | Record |
|---|---|---|---|---|
| Go | github.com/knadh/listmonk | >= 1.1.1, < 6.0.0 | 6.0.0 | GHSA-jmr4-p576-v565 |
| Go | github.com/knadh/listmonk | < 1.1.1-0.20251231125615-74dc5a01cfbb | 1.1.1-0.20251231125615-74dc5a01cfbb | GHSA-jmr4-p576-v565 |
Advisories 2
- openSUSE-SU-2026:21483-1 Security update for govulncheck-vulndb SUSE / openSUSE Security Updates · Jul 31, 2026
- SUSE-SU-2026:0142-1 Security update for govulncheck-vulndb SUSE / openSUSE Security Updates · Mar 23, 2026