Dnn.Platform - XSS (CVE-2025-64095)

CVE-2025-64095 is a critical vulnerability in DNN (DotNetNuke) prior to version 10.1.1 that allows unauthenticated users to upload files and overwrite existing content via the default HTML editor provider. This flaw can be exploited to deface websites or inject malicious XSS payloads, potentially leading to full site compromise and further attacks.

CrowdSec has been tracking this vulnerability and its exploits since 26th of November 2025.

CrowdSec network observations suggest that most exploitation of CVE-2025-64095 involves focused reconnaissance to identify viable targets. Attackers typically tailor their campaigns based on system exposure and configuration. It is unlikely that a given attack is accidental. CrowdSec network telemetry also shows that exploitation of CVE-2025-64095 has significantly declined over the past week. Attack volumes are well below the long-term average, suggesting attackers are rapidly losing interest. The vulnerability appears to be falling out of active use across most threat landscapes.

Attackers exploit the unrestricted file upload vulnerability by sending crafted POST requests to /Providers/HtmlEditorProviders/DNNConnect.CKE/Browser/FileUploader.ashx, allowing them to upload arbitrary files without authentication. This endpoint is targeted to overwrite or add files, enabling website defacement and potential XSS payload injection.