Medium
Security advisory
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.
- Products
- Not specified
- Affected versions
- Not specified
- Fixed versions
- Not specified
- CVEs
- CVE-2021-43794
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 31 Oct 2026, 12:00 UTC · Revision 1
Source evidence
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.
osv:CVE-2021-43794
Complete source record
{
"id": "c62a8be17014eefa7386da20ad5b34a9113decac04ebee114032607c4f093455",
"url": "https://osv.dev/vulnerability/CVE-2021-43794",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "CVE-2021-43794",
"summary": "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.",
"evidence": "osv:CVE-2021-43794",
"products": [],
"severity": "medium",
"structured": {
"id": "CVE-2021-43794",
"aliases": [
"BIT-discourse-2021-43794",
"CVE-2021-43794",
"GHSA-249g-pc77-65hp"
],
"metrics": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L"
}
],
"affected": [
{
"ranges": [
{
"repo": "https://github.com/discourse/discourse",
"type": "GIT",
"events": [
{
"introduced": "0"
},
{
"fixed": "30bc65af7036465001efc8c06b421e5098073538"
},
{
"fixed": "2da0001965c6d8632d723c46ea5df9f22a1a23f1"
}
],
"database_specific": {
"extracted_events": [
{
"cpe": "cpe:2.3:a:discourse:discourse:*:*:*:*:*:*:*:*",
"range": [
{
"introduced": "0"
},
{
"fixed": "2.7.11"
}
],
"source": "CPE_RANGE"
},
{
"range": [
{
"fixed": "2da0001965c6d8632d723c46ea5df9f22a1a23f1"
}
],
"source": "REFERENCES_COMMIT"
}
]
}
}
],
"versions": [
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],
"database_specific": {
"source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2021-43794.json"
}
}
],
"modified": "2026-10-20T10:55:04.026050407Z",
"provider": "osv",
"references": [
"https://github.com/discourse/discourse/security/advisories/GHSA-249g-pc77-65hp",
"https://github.com/discourse/discourse/commit/2da0001965c6d8632d723c46ea5df9f22a1a23f1"
],
"provider_metadata": {}
},
"related_cves": [
{
"value": "CVE-2021-43794",
"evidence": "/id"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 386817,
"published_at": "2021-12-01T20:15:08.727+00:00"
}