CVE-2021-43794

mediumpriority · track · 20EPSS 0.011 · 64 %ileEUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

1.05% (64th) EPSS

CVSS 5 · medium

Is it mine?

5 products

Check your exposure

Who says so?

4 sources

cnnvd · enisa_euvd · osv · nvd

EPSS · scored 2026-10-27

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

Technical severity, 0–10. One row per scoring source.

5.3

010

base score 0–10 · higher = more severe · hover a vector to decode

v2.05mediumAV:N/AC:L/Au:N/C:N/I:N/A:Pprimary · NVD / NIST USexploitability 10 · impact 2.9

v3.15.3mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Lsecondary · ENISA EU

v3.15.3mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Lsecondary · security-advisories@github.comexploitability 3.9 · impact 1.4

v3.14.9mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L/E:Usecondary · CVSS-BT (t0sche)

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-610US

affected products (5)

Products and version ranges known to be affected.

discourse discoursebeta → 2.8.0.beta9enisa_euvdEU
discourse discoursestable → 2.7.11enisa_euvdEU
discourse discoursetests-passed → 2.8.0.beta9enisa_euvdEU
discourse discourse< 2.7.11nvdUScpe:2.3:a:discourse:discourse:*:*:*:*:*:*:*:*
Bitnami discourse< 2.7.11osvUSpkg:bitnami/discourse

advisories (1)

Vendor and ecosystem advisories describing this.

BIT-discourse-2021-43794Anonymous user cache poisoning via development-mode header in Discourse2024-03-06vendor · osvUS
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.

also known as (3)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd osv nvd NVD CVE.org MITRE

published 2021-12-01modified 2026-06-17

references (7)

External citations — patches, advisories, analysis.

scry

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