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CVE-2026-128334 listmonk 6.2.0 before 7.0.0-beta.2 Missing Authentication via Azure Bounce Webhook

6.3 mediumEPSS 0.5%

Medium (6.3) in knadh listmonk. EPSS 0.5% estimated probability of exploitation activity in the next 30 days.

On this page
listmonk 6.2.0 before 7.0.0-beta.2 contains a missing authentication vulnerability that allows unauthenticated attackers to submit Azure Event Grid bounce webhooks when no shared secret is configured. Attackers can POST forged EmailDeliveryReportReceived events with Bounced status to /webhooks/service/azure to blocklist, unsubscribe, or delete arbitrary subscribers.

Severity

CVSS 4.0

6.3 medium
CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N

CVSS 3.1

4.8 medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:L
EPSS
0.5% estimated probability of exploitation activity in the next 30 days; 41st percentile. Scored 2026-11-13. A forecast for this CVE across the internet, not for your own systems.
CWE
CWE-636 Not Failing Securely (Failing Open)
OWASP Top 10
A10:2025 Mishandling of Exceptional Conditions
Published
Modified
Assigned by
VulnCheck (CNA)
NVD analysis
Deferred: the NVD does not plan to analyze it
Record from
the NVD, synced

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Affected

Versions

From the CNA's record in the CVE List.

ProductAffected
knadh listmonkfrom 6.2.0 before 7.0.0-beta.2

History

  1. The NVD deferred its analysis

Changes since this site first stored the record. The same for every record: /api/public/changes.

References

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