Discourse is an open source discussion platform. Prior to versions 2025.12.2, 2026.1.1, and 2026.2.0, a user full name can be evaluated as raw HTML when the following settings are set: display_name_on_posts => true; and prioritize_username_in_ux => false. Editing a post of a malicious user would trigger an XSS. Versions 2025.12.2, 2026.1.1, and 2026.2.0 patch the issue. No known workarounds are available.
{
"cwe_ids": [
"CWE-79"
],
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/27xxx/CVE-2026-27154.json",
"cna_assigner": "GitHub_M"
}{
"cpe": [
"cpe:2.3:a:discourse:discourse:*:*:*:*:*:*:*:*",
"cpe:2.3:a:discourse:discourse:2026.2.0:*:*:*:latest:*:*:*"
],
"extracted_events": [
{
"introduced": "0"
},
{
"fixed": "2025.12.2"
},
{
"introduced": "2026.1.0"
},
{
"fixed": "2026.1.1"
},
{
"introduced": "2026.2.0"
},
{
"last_affected": "2026.2.0"
}
],
"source": [
"CPE_RANGE",
"CPE_STRING"
]
}