What is the CVSS score of CVE-2025-53831?

CVE-2025-53831 has a CVSS 3.1 base score of 8.2 (High). CVSS vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:L/A:L. EPSS exploitation probability: 0.2%.

Which versions of DrawIO for ownCloud are affected by CVE-2025-53831?

DrawIO for ownCloud contains a stored cross-site scripting vulnerability (no public exploit currently identified) affecting authenticated users who can inject malicious code that executes in other…. A patch is available.

How to fix or mitigate CVE-2025-53831?

Within 24 hours: Inventory all ownCloud 10 deployments and confirm DrawIO app status (vulnerable if version prior to 1.0.2). Within 7 days: If vulnerable, either restrict DrawIO access to highly trusted users only, disable the application if not operationally critical, or upgrade ownCloud to version 10.15.3 or later; implement real-time session monitoring for anomalous activities. Within 30 days: Monitor vendor advisories for patched DrawIO versions; evaluate alternative deployment models (such as self-hosted draw.io with network isolation) that provide better session protection.

DrawIO for ownCloud CVE-2025-53831

EUVD-2025-210435 HIGH

Cross-site Scripting (XSS) (CWE-79)

2026-07-06 GitHub_M

XSS Drawio For Owncloud Owncloud 10

8.2

CVSS 3.1 · Vendor: GitHub_M

Severity by source

Vendor (GitHub_M) PRIMARY

8.2 HIGH

AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:L/A:L

vuln.today AI

5.4 MEDIUM

Requires an authenticated app user (PR:L) and victim interaction (UI:R); stored XSS crosses into the victim's browser context (S:C) with impact bounded to session/data there, so C:L/I:L and no availability effect.

3.1 AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N

4.0 AV:N/AC:L/AT:N/PR:L/UI:P/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N

Primary rating from Vendor (GitHub_M).

CVSS VectorVendor: GitHub_M

CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:L/A:L

Attack Vector

Network

Attack Complexity

Low

Privileges Required

Low

User Interaction

Required

Scope

Changed

Confidentiality

High

Integrity

Low

Availability

Low

Lifecycle Timeline

Patch available

Jul 06, 2026 - 18:02 EUVD

Analysis Generated

Jul 06, 2026 - 17:10 vuln.today

DescriptionCVE.org

DrawIO for ownCloud is an application for using DrawIO with the file storage, synchronization, and sharing application ownCloud Classic. In DrawIO for ownCloud prior to version 1.0.2, which corresponds to ownCloud 10 prior to version 10.15.3, attackers with access to the DrawIO app can leverage improper neutralization of input during web page generation to achieve stored XSS. Upgrade ownCloud 10 to version 10.15.3 or later or upgrade DrawIO for ownCloud 10 to version 1.0.2 or later to receive a patch.

AnalysisAI

Stored cross-site scripting in the DrawIO for ownCloud app (versions prior to 1.0.2, shipping with ownCloud 10 before 10.15.3) allows an authenticated user with access to the DrawIO app to persist a malicious payload that later executes in another user's browser session. Because the payload is stored and rendered to victims within the trusted ownCloud origin, it can hijack sessions or act on the victim's behalf. There is no public exploit identified at time of analysis and the flaw is not listed in CISA KEV.

Technical ContextAI

ownCloud Classic (ownCloud 10) is a self-hosted file storage, synchronization, and sharing platform; DrawIO for ownCloud is an add-on app that embeds the draw.io diagramming editor so diagrams can be created and stored alongside files. The root cause is CWE-79 (Improper Neutralization of Input During Web Page Generation): user-controlled input - such as diagram content, metadata, or names rendered by the app - is written into generated HTML without adequate output encoding or sanitization, so it is interpreted as active script. The two affected products identified via CPE are cpe:2.3:a:owncloud:drawio_for_owncloud (the app itself) and cpe:2.3:a:owncloud:owncloud_10 (the host platform that bundles it), confirming the vulnerable surface is the DrawIO app as integrated into the ownCloud 10 web UI.

RemediationAI

Apply the vendor-released patch: upgrade DrawIO for ownCloud to version 1.0.2 or later, or upgrade the host ownCloud 10 platform to version 10.15.3 or later, both of which contain the fix (see advisory GHSA-r9j8-fr2h-m47q at https://github.com/owncloud/security-advisories/security/advisories/GHSA-r9j8-fr2h-m47q). If immediate patching is not possible, the most direct compensating control is to disable or unload the DrawIO app from the ownCloud app management console, which removes the vulnerable surface entirely at the cost of losing diagram-editing functionality for all users. As secondary hardening, restrict which users can access the DrawIO app to trusted accounts only, reducing the pool of potential injectors, and enforce a strict Content-Security-Policy on the ownCloud origin to constrain script execution - accepting that CSP may break some legitimate embedded-editor behavior and is not a substitute for the patch.