Discourse is an open-source discussion platform. Prior to version 3.4.4 of the stable branch, version 3.5.0.beta5 of the beta branch, and version 3.5.0.beta6-dev of the tests-passed branch, Codepen is present in the default allowed_iframes site setting, and it can potentially auto-run arbitrary JS in the iframe scope, which is unintended. This issue is patched in version 3.4.4 of the stable branch, version 3.5.0.beta5 of the beta branch, and version 3.5.0.beta6-dev of the tests-passed branch. As a workaround, the Codepen prefix can be removed from a site's allowed_iframes.
{
"cwe_ids": [
"CWE-1038"
],
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/48xxx/CVE-2025-48877.json",
"cna_assigner": "GitHub_M"
}{
"cpe": [
"cpe:2.3:a:discourse:discourse:*:*:*:*:stable:*:*:*",
"cpe:2.3:a:discourse:discourse:*:*:*:*:beta:*:*:*",
"cpe:2.3:a:discourse:discourse:3.5.0:beta1:*:*:beta:*:*:*",
"cpe:2.3:a:discourse:discourse:3.5.0:beta2:*:*:beta:*:*:*",
"cpe:2.3:a:discourse:discourse:3.5.0:beta3:*:*:beta:*:*:*",
"cpe:2.3:a:discourse:discourse:3.5.0:beta4:*:*:beta:*:*:*"
],
"extracted_events": [
{
"introduced": "0"
},
{
"fixed": "3.4.4"
},
{
"fixed": "3.5.0"
},
{
"introduced": "3.5.0-beta1"
},
{
"last_affected": "3.5.0-beta1"
},
{
"introduced": "3.5.0-beta2"
},
{
"last_affected": "3.5.0-beta2"
},
{
"introduced": "3.5.0-beta3"
},
{
"last_affected": "3.5.0-beta3"
},
{
"introduced": "3.5.0-beta4"
},
{
"last_affected": "3.5.0-beta4"
}
],
"source": [
"CPE_RANGE",
"CPE_STRING"
]
}