CVE-2026-128334
listmonk 6.2.0 before 7.0.0-beta.2 Missing Authentication via Azure Bounce Webhook
Description
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.
INFO
Published Date :
Nov. 13, 2026, 10:18 a.m.
Last Modified :
Nov. 13, 2026, 10:18 a.m.
Remotely Exploit :
Yes !
Source :
[email protected]
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | MEDIUM | 83251b91-4cc7-4094-a5c7-464a1b83ea10 | ||||
| CVSS 3.1 | MEDIUM | MITRE-CVE | ||||
| CVSS 3.1 | MEDIUM | [email protected] | ||||
| CVSS 4.0 | MEDIUM | 83251b91-4cc7-4094-a5c7-464a1b83ea10 | ||||
| CVSS 4.0 | MEDIUM | [email protected] |
Solution
- Update Listmonk to version 7.0.0-beta.2 or later.
- Configure a shared secret for Azure Event Grid webhooks.
- Review and secure webhook configurations.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-128334.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-128334 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-128334
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-128334 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-128334 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
New CVE Received by [email protected]
Nov. 13, 2026
Action Type Old Value New Value Added Description 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. Added CVSS V4.0 AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X Added CVSS V3.1 AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:L Added CWE CWE-636 Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/128xxx/CVE-2026-128334.json">CVE-2026-128334</a> Added Reference https://github.com/biofool/listmonk/issues/5 Added Reference https://github.com/knadh/listmonk/blob/v7.0.0-beta.1/internal/bounce/webhooks/azure.go#L141-L149 Added Reference https://github.com/knadh/listmonk/commit/0c155bd2663d9ec8053ac0d1ab63f021fbb5a0dc Added Reference https://github.com/knadh/listmonk/releases/tag/v7.0.0-beta.2 Added Reference https://www.vulncheck.com/advisories/listmonk-6.2.0-before-7.0.0-beta.2-missing-authentication-via-azure-bounce-webhook