Discourse is an open-source discussion platform. Prior to 2026.7.0, the post action component failed to escape user-controlled display names before interpolating them into an HTML string passed to trustHTML. A user who could choose a crafted display name could persist markup in post action descriptions. Viewing the affected user activity streams could execute attacker-controlled script in another user's browser. This issue is fixed in version 2026.7.0.
{
"cna_assigner": "GitHub_M",
"cwe_ids": [
"CWE-79"
],
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/59xxx/CVE-2026-59830.json"
}{
"extracted_events": [
{
"range": [
{
"introduced": "0"
},
{
"fixed": "2026.7.0"
}
],
"source": "AFFECTED_FIELD",
"strategy": "StringRangeExpression"
},
{
"range": [
{
"fixed": "dd786594ddd088657a7e6f9fefba5bd889965fe4"
}
],
"source": "REFERENCES_COMMIT"
},
{
"original_tag": "v2026.7.0",
"range": [
{
"fixed": "ded677e00beb0e9bae6e70b69582aecfb72b5477"
}
],
"source": "REFERENCES_TAG"
}
]
}