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.

Insights from the CrowdSec network reveal that the attackers trying to exploit CVE-2025-64095 are composed of a fairly even mix of opportunistic and targeted actors. Some attackers employ preliminary reconnaissance, while others use indiscriminate scanning. In addition, according to the CrowdSec network, attack volume against CVE-2025-64095 has dipped slightly compared to the previous week. Although still commonly targeted, the decline suggests a cooling-off period. Long-term relevance remains, but attention is waning.

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.