Low
Discourse Vulnerable to Unauthorized Topic Creation in Staff-Only Categories via Topic Timer publish_to_category
Type: advisorySources: OSV
Discourse is an open source discussion platform. Prior to versions 2025.12.2, 2026.1.1, and 2026.2.0, TL4 users can publish topics into staff-only categories via the `publish_to_category` topic timer, bypassing authorization checks. Versions 2025.12.2, 2026.1.1, and 2026.2.0 patch the issue. No known workarounds are available.
- Products
- Not specified
- Affected versions
- Not specified
- Fixed versions
- Not specified
- CVEs
- CVE-2026-28227
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 3 Nov 2026, 13:51 UTC · Revision 1
Source evidence
Discourse Vulnerable to Unauthorized Topic Creation in Staff-Only Categories via Topic Timer publish_to_category
core-osv · Original sourcePublished 26 Feb 2026, 21:27 UTC
Discourse is an open source discussion platform. Prior to versions 2025.12.2, 2026.1.1, and 2026.2.0, TL4 users can publish topics into staff-only categories via the `publish_to_category` topic timer, bypassing authorization checks. Versions 2025.12.2, 2026.1.1, and 2026.2.0 patch the issue. No known workarounds are available.
osv:CVE-2026-28227
Complete source record
{
"id": "5787ce3434f165bf9cb0b1ed057cec7a4ece10c60f8ee57a54aca660a06a6e91",
"url": "https://osv.dev/vulnerability/CVE-2026-28227",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "Discourse Vulnerable to Unauthorized Topic Creation in Staff-Only Categories via Topic Timer publish_to_category",
"summary": "Discourse is an open source discussion platform. Prior to versions 2025.12.2, 2026.1.1, and 2026.2.0, TL4 users can publish topics into staff-only categories via the `publish_to_category` topic timer, bypassing authorization checks. Versions 2025.12.2, 2026.1.1, and 2026.2.0 patch the issue. No known workarounds are available.",
"evidence": "osv:CVE-2026-28227",
"products": [],
"severity": "low",
"structured": {
"id": "CVE-2026-28227",
"aliases": [
"BIT-discourse-2026-28227",
"CVE-2026-28227",
"GHSA-m49w-78mh-87jp"
],
"metrics": [
{
"type": "CVSS_V4",
"score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:U"
}
],
"affected": [
{
"ranges": [
{
"repo": "https://github.com/discourse/discourse",
"type": "GIT",
"events": [
{
"introduced": "0"
},
{
"fixed": "9c924c6f4f3885ab616e21bec2447af7056b4322"
},
{
"introduced": "322d3c0ac6a8f133b3f82875e9dbbe310f638c1b"
},
{
"fixed": "8a2a8b7d3a494435949a12ad078b22509f54bd58"
},
{
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},
{
"last_affected": "f7cec86997edc21d6074ceb7666f7e2e6e1b1fdf"
}
],
"database_specific": {
"extracted_events": [
{
"cpe": "cpe:2.3:a:discourse:discourse:*:*:*:*:*:*:*:*",
"range": [
{
"introduced": "0"
},
{
"fixed": "2025.12.2"
}
],
"source": "CPE_RANGE"
},
{
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"range": [
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"introduced": "2026.1.0"
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{
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"range": [
{
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{
"last_affected": "2026.2.0"
}
],
"source": "CPE_STRING"
}
]
}
}
],
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"database_specific": {
"source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-28227.json"
}
}
],
"modified": "2026-10-28T02:30:29.232669615Z",
"provider": "osv",
"references": [
"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/28xxx/CVE-2026-28227.json",
"https://github.com/discourse/discourse/security/advisories/GHSA-m49w-78mh-87jp",
"https://nvd.nist.gov/vuln/detail/CVE-2026-28227"
],
"provider_metadata": {
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],
"cna_assigner": "GitHub_M",
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/28xxx/CVE-2026-28227.json"
}
},
"related_cves": [
{
"value": "CVE-2026-28227",
"evidence": "/id"
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],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 496091,
"published_at": "2026-02-26T21:27:38.926+00:00"
}