CVE-2026-128334 json
listmonk 6.2.0 before 7.0.0-beta.2 Missing Authentication via Azure Bounce Webhook
published 2d ago modified 2d ago also EUVD-2026-125043
- cvss
- 4.8
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.4%
- EPSS 0.4% chance of exploitation in 30 days, percentile 30%
- public exploits
- 0
- none known
Summary
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.
Patch / fix
- knadh listmonk 7.0.0-beta.2
Is CVE-2026-128334 in your stack? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.
Check with FencerExploit prediction
0.37% chance of exploitation in the next 30 days, higher than 30% of all scored CVEs (FIRST EPSS, 2026-11-14).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 6.3 | 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 |
| CNA | 3.1 | 4.8 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:L |
| CNA | 4.0 | 6.3 | 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/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 |
| NVD | 3.1 | 4.8 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:L |
Affected products
- knadh listmonk
Classification
- Weakness
-
- CWE-636 Not Failing Securely
References
-
github.com
/knadh/listmonk/commit/0c155bd2663d9ec8053ac0d1ab63f021fbb5a0dc
patch
-
github.com
/knadh/listmonk/releases/tag/v7.0.0-beta.2
release-notes
-
github.com
/knadh/listmonk/blob/v7.0.0-beta.1/internal/bounce/webhooks/azure.go#L141-L149
technical-description
-
github.com
/biofool/listmonk/issues/5
issue-tracking
-
vulncheck.com
/advisories/listmonk-6.2.0-before-7.0.0-beta.2-missing-authentication-via-azure-bounce-webhook
third-party-advisory
Sources
- CVE List CVE-2026-128334
- NVD CVE-2026-128334
Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.