VDB
CVE-2021-34431
CVE-2021-34431
PUBLISHED
Reported by eclipse · Published July 22, 2021
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.
Fixed versions
Upgrade to a fixed version or later. Language registries are listed first, then Linux distributions, then vendor products.
| Package | Ecosystem | Fixed in |
|---|---|---|
| mosquitto | Ubuntu:Pro:20.04:LTS | 1.6.9-1ubuntu0.1~esm1 |
| mosquitto | eclipse | 2.0.10 |
| Eclipse Mosquitto | The Eclipse Foundation | unspecified, 2.0.10 |
Affected products
| Vendor | Product | Versions |
|---|---|---|
| The Eclipse Foundation | Eclipse Mosquitto | 1.6, unspecified |
| The Eclipse Foundation | Eclipse Mosquitto | 1.6, * |
Timeline
- Jul 22, 2021 CVE Published
- Jul 23, 2021 EPSS Score (30 in total, the first dated here)
- Aug 4, 2024 CVE Updated
- Mar 7, 2026 Distribution Patch
- Mar 7, 2026 Security Advisory (2 in total, the first dated here)
- Jul 30, 2026 Coalition ESS Score
Query this with the API
The same record, from the CLI:
vulnetix vdb vuln CVE-2021-34431
vulnetix vdb fixes CVE-2021-34431Or with curl, using the org id and key from your account page:
curl -s -H "Authorization: ApiKey ${VULNETIX_ORG_ID}:${VULNETIX_API_KEY}" \
"https://api.vdb.vulnetix.com/v2/vuln/CVE-2021-34431/fixes/registry"The Community plan is free and allows 50 queries a day. Get a free API key · API quickstart