Description
In Eclipse Mosquitto version 1.6 to 2.0.10, if an authenticated client that had connected with MQTT v5 sent a crafted CONNECT message to the broker a memory leak would occur, which could be used to provide a DoS attack against the broker.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| The Eclipse Foundation | Eclipse Mosquitto | 1.6 – < unspecified, unspecified – ≤ 2.0.10 | unspecified |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | mosquitto | 2.0.11-1 | — |
| Debian 13 | mosquitto | 2.0.11-1 | — |
| Debian 12 | mosquitto | 2.0.11-1 | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 22.04 LTS | mosquitto | 2.0.11-1ubuntu1.1 | USN-6492-1 |
Show 1 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 20.04 LTS | mosquitto | 1.6.9-1ubuntu0.1~esm1 | USN-6492-1 |
Advisories 2
- USN-6492-1 mosquitto vulnerabilities Ubuntu Security Notices (USN) · Apr 22, 2026
- WID-SEC-2023-1094 IBM Integration Bus: Mehrere Schwachstellen ermöglichen Denial of Service BSI CERT-Bund (WID) · Apr 27, 2023