CVE catalog
CVE-2021-28166
mosquitto: CVE-2021-28166
- Severity
- Medium · CVSS 6.5
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H - Published
- Source
- [NVD] · [CVE record]
- EPSS
- 0.97% · Oct 25, 2026
In Eclipse Mosquitto version 2.0.0 to 2.0.9, if an authenticated client that had connected with MQTT v5 sent a crafted CONNACK message to the broker, a NULL pointer dereference would occur.
Vulnerable and fixed packages
Distribution-reported package versions and fixes. These do not depend on matching against the OpenFactory package catalog.
| Distribution | Package | Release | Version | Status |
|---|---|---|---|---|
| Debian | mosquitto | sid | 2.1.2-3 | fixed |
| Debian | mosquitto | forky | 2.1.2-3 | fixed |
| Debian | mosquitto | trixie | 2.0.21-1 | fixed |
| Debian | mosquitto | bookworm | 2.0.11-1.2+deb12u2 | fixed |
| Debian | mosquitto | bookworm-security | 2.0.11-1.2+deb12u1 | fixed |
| Alpine | mosquitto | 3.14 | 2.0.10-r0 | fixed |
| Alpine | mosquitto | 3.15 | 2.0.10-r0 | fixed |
| Alpine | mosquitto | 3.16 | 2.0.10-r0 | fixed |
| Alpine | mosquitto | 3.17 | 2.0.10-r0 | fixed |
| Alpine | mosquitto | 3.18 | 2.0.10-r0 | fixed |
| Alpine | mosquitto | 3.19 | 2.0.10-r0 | fixed |
| Alpine | mosquitto | 3.20 | 2.0.10-r0 | fixed |
| Alpine | mosquitto | 3.21 | 2.0.10-r0 | fixed |
| Alpine | mosquitto | 3.22 | 2.0.10-r0 | fixed |
| Alpine | mosquitto | 3.23 | 2.0.10-r0 | fixed |
| Alpine | mosquitto | 3.24 | 2.0.10-r0 | fixed |
Fixed-version evidence
| Distribution | Package | Type | Release | Fixed version | Urgency | Origin | Bugs |
|---|---|---|---|---|---|---|---|
| Debian | mosquitto | source | sid | 2.0.10-1 | not yet assigned | Not reported | [986701] |
| Debian | mosquitto | source | forky | 2.0.10-1 | not yet assigned | Not reported | [986701] |
| Debian | mosquitto | source | trixie | 2.0.10-1 | not yet assigned | Not reported | [986701] |
| Debian | mosquitto | source | bookworm | 2.0.10-1 | not yet assigned | Not reported | [986701] |
| Alpine | mosquitto | apk | 3.14 | 2.0.10-r0 | Not reported | ALPINE-CVE-2021-28166 | Not reported |
| Alpine | mosquitto | apk | 3.15 | 2.0.10-r0 | Not reported | ALPINE-CVE-2021-28166 | Not reported |
| Alpine | mosquitto | apk | 3.16 | 2.0.10-r0 | Not reported | ALPINE-CVE-2021-28166 | Not reported |
| Alpine | mosquitto | apk | 3.17 | 2.0.10-r0 | Not reported | ALPINE-CVE-2021-28166 | Not reported |
| Alpine | mosquitto | apk | 3.18 | 2.0.10-r0 | Not reported | ALPINE-CVE-2021-28166 | Not reported |
| Alpine | mosquitto | apk | 3.19 | 2.0.10-r0 | Not reported | ALPINE-CVE-2021-28166 | Not reported |
| Alpine | mosquitto | apk | 3.20 | 2.0.10-r0 | Not reported | ALPINE-CVE-2021-28166 | Not reported |
| Alpine | mosquitto | apk | 3.21 | 2.0.10-r0 | Not reported | ALPINE-CVE-2021-28166 | Not reported |
| Alpine | mosquitto | apk | 3.22 | 2.0.10-r0 | Not reported | ALPINE-CVE-2021-28166 | Not reported |
| Alpine | mosquitto | apk | 3.23 | 2.0.10-r0 | Not reported | ALPINE-CVE-2021-28166 | Not reported |
| Alpine | mosquitto | apk | 3.24 | 2.0.10-r0 | Not reported | ALPINE-CVE-2021-28166 | Not reported |
OpenFactory catalog packages
[Debian 12 (Bookworm)]
- [libmosquitto1]Fixed
Source package: [mosquitto]
Details (6)
2.0.11-1.2+deb12u2· amd64 · bookwormFixed · Fixed:
2.0.10-1dsa · mosquitto · debian · bookworm; dsa · mosquitto · debian · 12
2.0.11-1.2+deb12u2· arm64 · bookwormFixed · Fixed:
2.0.10-1dsa · mosquitto · debian · bookworm; dsa · mosquitto · debian · 12
2.0.21-1~bpo12+1· amd64 · bookworm-backportsFixed · Fixed:
2.0.10-1dsa · mosquitto · debian · bookworm; dsa · mosquitto · debian · 12
2.0.21-1~bpo12+1· arm64 · bookworm-backportsFixed · Fixed:
2.0.10-1dsa · mosquitto · debian · bookworm; dsa · mosquitto · debian · 12
2.0.11-1.2+deb12u1· amd64 · bookworm-securityFixed · Fixed:
2.0.10-1dsa · mosquitto · debian · bookworm; dsa · mosquitto · debian · 12
2.0.11-1.2+deb12u1· arm64 · bookworm-securityFixed · Fixed:
2.0.10-1dsa · mosquitto · debian · bookworm; dsa · mosquitto · debian · 12
- [libmosquitto-dev]Fixed
Source package: [mosquitto]
Details (6)
2.0.11-1.2+deb12u2· amd64 · bookwormFixed · Fixed:
2.0.10-1dsa · mosquitto · debian · bookworm; dsa · mosquitto · debian · 12
2.0.11-1.2+deb12u2· arm64 · bookwormFixed · Fixed:
2.0.10-1dsa · mosquitto · debian · bookworm; dsa · mosquitto · debian · 12
2.0.21-1~bpo12+1· amd64 · bookworm-backportsFixed · Fixed:
2.0.10-1dsa · mosquitto · debian · bookworm; dsa · mosquitto · debian · 12
2.0.21-1~bpo12+1· arm64 · bookworm-backportsFixed · Fixed:
2.0.10-1dsa · mosquitto · debian · bookworm; dsa · mosquitto · debian · 12
2.0.11-1.2+deb12u1· amd64 · bookworm-securityFixed · Fixed:
2.0.10-1dsa · mosquitto · debian · bookworm; dsa · mosquitto · debian · 12
2.0.11-1.2+deb12u1· arm64 · bookworm-securityFixed · Fixed:
2.0.10-1dsa · mosquitto · debian · bookworm; dsa · mosquitto · debian · 12
- [libmosquittopp1]Fixed
Source package: [mosquitto]
Details (6)
2.0.11-1.2+deb12u2· amd64 · bookwormFixed · Fixed:
2.0.10-1dsa · mosquitto · debian · bookworm; dsa · mosquitto · debian · 12
2.0.11-1.2+deb12u2· arm64 · bookwormFixed · Fixed:
2.0.10-1dsa · mosquitto · debian · bookworm; dsa · mosquitto · debian · 12
2.0.21-1~bpo12+1· amd64 · bookworm-backportsFixed · Fixed:
2.0.10-1dsa · mosquitto · debian · bookworm; dsa · mosquitto · debian · 12
2.0.21-1~bpo12+1· arm64 · bookworm-backportsFixed · Fixed:
2.0.10-1dsa · mosquitto · debian · bookworm; dsa · mosquitto · debian · 12
2.0.11-1.2+deb12u1· amd64 · bookworm-securityFixed · Fixed:
2.0.10-1dsa · mosquitto · debian · bookworm; dsa · mosquitto · debian · 12
2.0.11-1.2+deb12u1· arm64 · bookworm-securityFixed · Fixed:
2.0.10-1dsa · mosquitto · debian · bookworm; dsa · mosquitto · debian · 12
- [libmosquittopp-dev]Fixed
Source package: [mosquitto]
Details (6)
2.0.11-1.2+deb12u2· amd64 · bookwormFixed · Fixed:
2.0.10-1dsa · mosquitto · debian · bookworm; dsa · mosquitto · debian · 12
2.0.11-1.2+deb12u2· arm64 · bookwormFixed · Fixed:
2.0.10-1dsa · mosquitto · debian · bookworm; dsa · mosquitto · debian · 12
2.0.21-1~bpo12+1· amd64 · bookworm-backportsFixed · Fixed:
2.0.10-1dsa · mosquitto · debian · bookworm; dsa · mosquitto · debian · 12
2.0.21-1~bpo12+1· arm64 · bookworm-backportsFixed · Fixed:
2.0.10-1dsa · mosquitto · debian · bookworm; dsa · mosquitto · debian · 12
2.0.11-1.2+deb12u1· amd64 · bookworm-securityFixed · Fixed:
2.0.10-1dsa · mosquitto · debian · bookworm; dsa · mosquitto · debian · 12
2.0.11-1.2+deb12u1· arm64 · bookworm-securityFixed · Fixed:
2.0.10-1dsa · mosquitto · debian · bookworm; dsa · mosquitto · debian · 12
- [mosquitto]Fixed
Details (6)
2.0.11-1.2+deb12u2· amd64 · bookwormFixed · Fixed:
2.0.10-1dsa · mosquitto · debian · bookworm; dsa · mosquitto · debian · 12
2.0.11-1.2+deb12u2· arm64 · bookwormFixed · Fixed:
2.0.10-1dsa · mosquitto · debian · bookworm; dsa · mosquitto · debian · 12
2.0.21-1~bpo12+1· amd64 · bookworm-backportsFixed · Fixed:
2.0.10-1dsa · mosquitto · debian · bookworm; dsa · mosquitto · debian · 12
2.0.21-1~bpo12+1· arm64 · bookworm-backportsFixed · Fixed:
2.0.10-1dsa · mosquitto · debian · bookworm; dsa · mosquitto · debian · 12
2.0.11-1.2+deb12u1· amd64 · bookworm-securityFixed · Fixed:
2.0.10-1dsa · mosquitto · debian · bookworm; dsa · mosquitto · debian · 12
2.0.11-1.2+deb12u1· arm64 · bookworm-securityFixed · Fixed:
2.0.10-1dsa · mosquitto · debian · bookworm; dsa · mosquitto · debian · 12
- [mosquitto-clients]Fixed
Source package: [mosquitto]
Details (6)
2.0.11-1.2+deb12u2· amd64 · bookwormFixed · Fixed:
2.0.10-1dsa · mosquitto · debian · bookworm; dsa · mosquitto · debian · 12
2.0.11-1.2+deb12u2· arm64 · bookwormFixed · Fixed:
2.0.10-1dsa · mosquitto · debian · bookworm; dsa · mosquitto · debian · 12
2.0.21-1~bpo12+1· amd64 · bookworm-backportsFixed · Fixed:
2.0.10-1dsa · mosquitto · debian · bookworm; dsa · mosquitto · debian · 12
2.0.21-1~bpo12+1· arm64 · bookworm-backportsFixed · Fixed:
2.0.10-1dsa · mosquitto · debian · bookworm; dsa · mosquitto · debian · 12
2.0.11-1.2+deb12u1· amd64 · bookworm-securityFixed · Fixed:
2.0.10-1dsa · mosquitto · debian · bookworm; dsa · mosquitto · debian · 12
2.0.11-1.2+deb12u1· arm64 · bookworm-securityFixed · Fixed:
2.0.10-1dsa · mosquitto · debian · bookworm; dsa · mosquitto · debian · 12
- [mosquitto-dev]Fixed
Source package: [mosquitto]
Details (6)
2.0.11-1.2+deb12u2· all · bookwormFixed · Fixed:
2.0.10-1dsa · mosquitto · debian · bookworm; dsa · mosquitto · debian · 12
2.0.11-1.2+deb12u2· all · bookwormFixed · Fixed:
2.0.10-1dsa · mosquitto · debian · bookworm; dsa · mosquitto · debian · 12
2.0.21-1~bpo12+1· all · bookworm-backportsFixed · Fixed:
2.0.10-1dsa · mosquitto · debian · bookworm; dsa · mosquitto · debian · 12
2.0.21-1~bpo12+1· all · bookworm-backportsFixed · Fixed:
2.0.10-1dsa · mosquitto · debian · bookworm; dsa · mosquitto · debian · 12
2.0.11-1.2+deb12u1· all · bookworm-securityFixed · Fixed:
2.0.10-1dsa · mosquitto · debian · bookworm; dsa · mosquitto · debian · 12
2.0.11-1.2+deb12u1· all · bookworm-securityFixed · Fixed:
2.0.10-1dsa · mosquitto · debian · bookworm; dsa · mosquitto · debian · 12
[Debian 13 (Trixie)]
- [libmosquitto1]Fixed
Source package: [mosquitto]
Details (2)
2.0.21-1· amd64 · trixieFixed · Fixed:
2.0.10-1dsa · mosquitto · debian · 13
2.0.21-1· arm64 · trixieFixed · Fixed:
2.0.10-1dsa · mosquitto · debian · 13
- [libmosquitto-dev]Fixed
Source package: [mosquitto]
Details (2)
2.0.21-1· amd64 · trixieFixed · Fixed:
2.0.10-1dsa · mosquitto · debian · 13
2.0.21-1· arm64 · trixieFixed · Fixed:
2.0.10-1dsa · mosquitto · debian · 13
- [libmosquittopp1]Fixed
Source package: [mosquitto]
Details (2)
2.0.21-1· amd64 · trixieFixed · Fixed:
2.0.10-1dsa · mosquitto · debian · 13
2.0.21-1· arm64 · trixieFixed · Fixed:
2.0.10-1dsa · mosquitto · debian · 13
- [libmosquittopp-dev]Fixed
Source package: [mosquitto]
Details (2)
2.0.21-1· amd64 · trixieFixed · Fixed:
2.0.10-1dsa · mosquitto · debian · 13
2.0.21-1· arm64 · trixieFixed · Fixed:
2.0.10-1dsa · mosquitto · debian · 13
- [mosquitto]Fixed
Details (2)
2.0.21-1· amd64 · trixieFixed · Fixed:
2.0.10-1dsa · mosquitto · debian · 13
2.0.21-1· arm64 · trixieFixed · Fixed:
2.0.10-1dsa · mosquitto · debian · 13
- [mosquitto-clients]Fixed
Source package: [mosquitto]
Details (2)
2.0.21-1· amd64 · trixieFixed · Fixed:
2.0.10-1dsa · mosquitto · debian · 13
2.0.21-1· arm64 · trixieFixed · Fixed:
2.0.10-1dsa · mosquitto · debian · 13
- [mosquitto-dev]Fixed
Source package: [mosquitto]
Details (2)
2.0.21-1· all · trixieFixed · Fixed:
2.0.10-1dsa · mosquitto · debian · 13
2.0.21-1· all · trixieFixed · Fixed:
2.0.10-1dsa · mosquitto · debian · 13
Observed:
References
- [https://ftp.suse.com/pub/projects/security/csaf/opensuse-su-2024_11057-1.json]
- [https://osv.dev/vulnerability/ALPINE-CVE-2021-28166]
- [https://osv.dev/vulnerability/DEBIAN-CVE-2021-28166]
- [https://osv.dev/vulnerability/UBUNTU-CVE-2021-28166]
- [https://security-tracker.debian.org/tracker/CVE-2021-28166]
[Debian Security Tracker] · [FIRST EPSS] · [OSV Package Vulnerability Database] · [SUSE security advisories and VEX]