CVE-2025-66512
BaseFortify
Publication date: 2025-12-05
Last updated on: 2025-12-09
Assigner: GitHub, Inc.
Description
Description
CVSS Scores
EPSS Scores
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Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| nextcloud | nextcloud_server | From 31.0.0 (inc) to 31.0.12 (exc) |
| nextcloud | nextcloud_server | From 31.0.0 (inc) to 31.0.12 (exc) |
| nextcloud | nextcloud_server | From 32.0.0 (inc) to 32.0.3 (exc) |
| nextcloud | nextcloud_server | From 32.0.0 (inc) to 32.0.3 (exc) |
Helpful Resources
Exploitability
| CWE ID | Description |
|---|---|
| CWE-79 | The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users. |
| CWE-80 | The product receives input from an upstream component, but it does not neutralize or incorrectly neutralizes special characters such as "<", ">", and "&" that could be interpreted as web-scripting elements when they are sent to a downstream component that processes web pages. |
Attack-Flow Graph
AI Powered Q&A
Can you explain this vulnerability to me?
This vulnerability in Nextcloud Server allows a malicious user to bypass the content security policy by tricking another user into viewing a specially crafted SVG file outside of the Nextcloud Server's web page. The issue is due to missing sanitization of the SVG content in versions prior to 31.0.12 and 32.0.3.
How can this vulnerability impact me? :
The vulnerability can lead to a partial security bypass where an attacker can circumvent content security policies, potentially leading to limited integrity and availability impacts on the affected system. This could allow malicious content to be executed or displayed in unintended ways when a user views a manipulated SVG file.
What immediate steps should I take to mitigate this vulnerability?
To mitigate this vulnerability, you should immediately upgrade your Nextcloud Server or Nextcloud Enterprise Server to version 31.0.12 or 32.0.3 or later, where the issue has been patched. There are no available workarounds, so applying the official update is the recommended action to prevent exploitation. [3]