CVE-2021-43850: Denial of Service in discourse

Published Jan 4, 2022
·
Updated

Discourse is an open source platform for community discussion. In affected versions admins users can trigger a Denial of Service attack via the /message-bus/diagnostics path. The impact of this vulnerability is greater on multisite Discourse instances (where multiple forums are served from a single application server) where any admin user on any of the forums are able to visit the /message-bus/diagnostics path. The problem has been patched. Please upgrade to 2.8.0.beta10 or 2.7.12. No workarounds for this issue exist.

Affected Software

10 affected components
Discourse Discourse<2.7.12
Discourse Discourse=2.8.0-beta1
Discourse Discourse=2.8.0-beta2
Discourse Discourse=2.8.0-beta3
Discourse Discourse=2.8.0-beta4
Discourse Discourse=2.8.0-beta5
Discourse Discourse=2.8.0-beta6
Discourse Discourse=2.8.0-beta7
Discourse Discourse=2.8.0-beta8
Discourse Discourse=2.8.0-beta9

Event History

Jan 4, 2022
CVE Published
via MITRE·07:35 PM
Data Sourced
via MITRE·07:35 PM
DescriptionSeverityWeakness
Data Sourced
via NVD·08:15 PM
RemedyDescriptionSeverityWeaknessAffected Software

Frequently Asked Questions

1

What is the severity of CVE-2021-43850?

CVE-2021-43850 has the potential to cause a Denial of Service attack, especially impacting multisite Discourse instances.

2

How do I fix CVE-2021-43850?

To remediate CVE-2021-43850, update Discourse to a version greater than 2.7.12 or use the latest beta release.

3

Which versions of Discourse are affected by CVE-2021-43850?

Versions of Discourse up to 2.7.12 and certain 2.8.0 beta releases are affected by CVE-2021-43850.

4

Can CVE-2021-43850 affect multisite Discourse installations?

Yes, CVE-2021-43850 poses a greater risk for multisite Discourse installations.

5

What specific functionality is exploited in CVE-2021-43850?

CVE-2021-43850 can be exploited via the '/message-bus/_diagnostics' path to trigger a Denial of Service.

Contact

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