CVE-2025-59788: Cross-site scripting (XSS) vulnerability in a reachable files_pdfviewer example directory in Nextcloud with versions…
CVE-2025-59788 · Severity: medium · CVSS 6.4 · Published 2025-12-04
Cross-site scripting (XSS) vulnerability in a reachable files_pdfviewer example directory in Nextcloud with versions before 22.2.10.33, 23.0.12.29, 24.0.12.28, 25.0.13.23, 26.0.13.20, 27.1.11.20, 28.0.14.11, 29.0.16.8, 30.0.17, 31.0.10, and 32.0.1 allows attackers to execute arbitrary JavaScript in the context of a user's browser via a crafted PDF file to viewer.html. This issue is related to CVE-2024-4367, but the root cause of this Nextcloud issue is that the product exposes executable example code on a same-origin basis.
No. Junglewise Threat Intelligence has no report of CVE-2025-59788 being exploited in the wild.
How severe is CVE-2025-59788?
Medium severity, with a CVSS score of 6.4, published 4 December 2025.
Which products and versions are affected?
Nextcloud Server. The advisory does not name versions.
Is there a fix for CVE-2025-59788?
No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
Am I affected by CVE-2025-59788?
Check whether you run Nextcloud Server. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.