Using show_inline=1 parameter and a valid file_showinlinetoken CSRF token on file_download.php, an attacker can execute code by uploading a crafted XHTML attachment referencing a JavaScript attachment.
Cross-site scripting
None
Thanks to siunam (Tang Cheuk Hei) for discovering and responsibly reporting the issue.
{
"github_reviewed": true,
"github_reviewed_at": "2026-05-11T19:40:43Z",
"cwe_ids": [
"CWE-79"
],
"severity": "HIGH",
"nvd_published_at": null
}