Vulnerability · Published Sep 23, 2026 · Assigned by GitHub_M
CVE-2026-95844Moquette deeply nested MQTT topics can cause stack exhaustion
High 8.7
In plain English
A high-severity security flaw in moquette from moquette-io. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 37% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
Moquette is a lightweight Java MQTT broker. Prior to 0.18.1, Moquette does not limit the depth of topic names and topic filters before processing them through recursive CTrie insertion and matching operations. A remote client can publish or subscribe with a deeply nested topic, causing a StackOverflowError that disrupts session processing and can deny service to broker clients. This issue is fixed in version 0.18.1.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Maven | io.moquette:moquette-broker | 0.18.1 | GHSA-5f42-97gr-vfhq |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| moquette-io | moquette | < 0.18.1 |
Weakness: CWE-674 · Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N