Medium severity · published Jan 4, 2022
CVE-2021-43850
Discourse is an open source platform for community discussion
6.8
CVSS
0.8%
EPSS
No
On KEV
Description
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
High
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)0.8% · higher than 57% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
DI
Discourse · Discourse
before 2.7.12; 2.8.0; 2.8.0; 2.8.0; 2.8.0; 2.8.0; +4 more · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-43850
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-43850
Patch
https://github.com/discourse/discourse/commit/7a8ec129fb54f188b2da6588c9d24d3a36eb0d39
Exploit
https://github.com/discourse/discourse/security/advisories/GHSA-59jr-pj65-qmvr
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