Medium severity · published Dec 1, 2021
CVE-2021-43794
Discourse is an open source discussion platform
5.3
CVSS
1%
EPSS
No
On KEV
Description
Discourse is an open source discussion platform. In affected versions an attacker can poison the cache for anonymous (i.e. not logged in) users, such that the users are shown a JSON blob instead of the HTML page. This can lead to a partial denial-of-service. This issue is patched in the latest stable, beta and tests-passed versions of Discourse.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
Low
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)1.0% · higher than 64% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
DI
Discourse · Discourse
before 2.7.11 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-43794
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-43794
Patch
https://github.com/discourse/discourse/commit/2da0001965c6d8632d723c46ea5df9f22a1a23f1
Third Party Advisory
https://github.com/discourse/discourse/security/advisories/GHSA-249g-pc77-65hp
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