CVE-2021-43850
What it is
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.
At a glance
- Exploitability
- Can be exploited over the network with a low-privilege account, but needs a user to act. High risk of service disruption.
- Exploit odds
- 0.9% chance of exploitation in the next 30 days (EPSS).
- Fix
- A patch, advisory or fixed version is referenced. Upgrade or apply it.
Timeline
- PublishedDisclosed publicly on CVE.org and NVD
- Last updatedMost recent change to the record
Why it ranks here
- Exploited in the wild: no, CISA does not list it.
- Exploit odds: 0.9% in the next 30 days (EPSS).
- Severity: 6.8 MEDIUM (CVSS).
- Fix: a patch or advisory is linked.
Details
- Published
- Last modified
- Exploit probability
- 0.9% · EPSS, next 30 days
- Weakness
- CWE-20 · Improper input validation
- Record status
- Modified
Affected
- Discourse < 2.7.12
- Discourse 2.8.0
Attack profile CVSS 3.1 · 6.8
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- Required
- Scope
- Changed
- Confidentiality
- None
- Integrity
- None
- Availability
- High
Raw vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:N/I:N/A:H
Is it in your code?
Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.
Read https://cve-list.com/agent/cve/CVE-2021-43850.md and follow it. Check whether this project is affected by CVE-2021-43850. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.
Fix and advisories
- https://github.com/discourse/discourse/commit/7a8ec129fb54f188b2da6588c9d24d3a36eb0d39
- https://github.com/discourse/discourse/security/advisories/GHSA-59jr-pj65-qmvr
- https://github.com/discourse/discourse/commit/7a8ec129fb54f188b2da6588c9d24d3a36eb0d39
- https://github.com/discourse/discourse/security/advisories/GHSA-59jr-pj65-qmvr
References
- https://github.com/discourse/discourse/commit/7a8ec129fb54f188b2da6588c9d24d3a36eb0d39
- https://github.com/discourse/discourse/security/advisories/GHSA-59jr-pj65-qmvr
- https://github.com/discourse/discourse/commit/7a8ec129fb54f188b2da6588c9d24d3a36eb0d39
- https://github.com/discourse/discourse/security/advisories/GHSA-59jr-pj65-qmvr