How severe is CVE-2026-34584?

CVE-2026-34584 has a CVSS 3.x base score of 5.4, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2026-34584 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (7th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-34584?

CVE-2026-34584 affects Nadh Listmonk. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-34584?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2026-34584 have an EU (EUVD) identifier?

Yes. CVE-2026-34584 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-18450.

When was CVE-2026-34584 published?

CVE-2026-34584 was published on 2026-04-02 and last updated on 2026-06-17.

CVE-2026-34584

CVE-2026-34584 is a medium-severity vulnerability in Nadh Listmonk with a CVSS 3.x base score of 5.4. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-639.

Key facts

Severity: Medium (CVSS 3.x base score 5.4)
EPSS exploit prediction: 0% (7th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-18450
Weakness: CWE-639
Affected product: Nadh Listmonk
Published: 2026-04-02
Last modified: 2026-06-17

Description

listmonk is a standalone, self-hosted, newsletter and mailing list manager. From version 4.1.0 to before version 6.1.0, bugs in list permission checks allows users in a multi-user environment to access to lists (which they don't have access to) under different scenarios. This only affects multi-user environments with untrusted users. This issue has been patched in version 6.1.0.

Frequently asked questions

What is CVE-2026-34584?: listmonk is a standalone, self-hosted, newsletter and mailing list manager. From version 4.1.0 to before version 6.1.0, bugs in list permission checks allows users in a multi-user environment to access to lists (which they don't have access to) under different scenarios. This only affects multi-user environments with untrusted users. This issue has been patched in version 6.1.0.
How severe is CVE-2026-34584?: CVE-2026-34584 has a CVSS 3.x base score of 5.4, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2026-34584 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (7th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-34584?: CVE-2026-34584 affects Nadh Listmonk. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-34584?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-34584 have an EU (EUVD) identifier?: Yes. CVE-2026-34584 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-18450.
When was CVE-2026-34584 published?: CVE-2026-34584 was published on 2026-04-02 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:nadh:listmonk:*:*:*:*:*:*:*:*

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