YOURLS is a self-hosted, customizable URL shortener written in PHP. From 1.5.1 until 1.10.4, YOURLS stores the HTTP Referer header through yourls_get_referrer(), yourls_sanitize_url_safe(), and yourls_log_redirect(), then aggregates the value in yourls-infos.php and passes the derived domain through yourls_get_domain(), yourls_stats_pie(), and yourls_google_array_to_data_table(). The chart builder concatenates labels into inline JavaScript without JavaScript-string escaping, so an unauthenticated attacker can poison the statistics of an existing short URL with a crafted referrer. When an administrator or public stats-page viewer opens the affected statistics page, attacker-controlled JavaScript executes in the YOURLS origin and can access admin-visible data, the API signature token, and privileged same-origin actions. This issue is fixed in version 1.10.4.
{
"cna_assigner": "GitHub_M",
"cwe_ids": [
"CWE-79"
],
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/63xxx/CVE-2026-63135.json"
}{
"extracted_events": [
{
"range": [
{
"introduced": "1.5.1"
},
{
"fixed": "1.10.4"
}
],
"source": "AFFECTED_FIELD",
"strategy": "StringRangeExpression"
},
{
"range": [
{
"fixed": "e1e93476655107e6caab34e52259eb1c91079ec7"
}
],
"source": "REFERENCES_COMMIT"
},
{
"original_tag": "1.10.4",
"range": [
{
"fixed": "ef695ea14d89d920e771a88f32cbe0485256366a"
}
],
"source": "REFERENCES_TAG"
}
]
}