How severe is CVE-2025-59788?

CVE-2025-59788 has a CVSS 3.x base score of 6.4, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2025-59788 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (17th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2025-59788?

CVE-2025-59788 primarily affects Nextcloud Nextcloud Server. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2025-59788?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2025-59788 have an EU (EUVD) identifier?

Yes. CVE-2025-59788 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-201255.

When was CVE-2025-59788 published?

CVE-2025-59788 was published on 2025-12-04 and last updated on 2026-06-17.

CVE-2025-59788

CVE-2025-59788 is a medium-severity vulnerability in Nextcloud Nextcloud Server with a CVSS 3.x base score of 6.4. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-79.

Key facts

Severity: Medium (CVSS 3.x base score 6.4)
EPSS exploit prediction: 0% (17th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2025-201255
Weakness: CWE-79
Affected product: Nextcloud Nextcloud Server
Published: 2025-12-04
Last modified: 2026-06-17

Description

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.

Frequently asked questions

What is CVE-2025-59788?: 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.
How severe is CVE-2025-59788?: CVE-2025-59788 has a CVSS 3.x base score of 6.4, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2025-59788 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (17th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-59788?: CVE-2025-59788 primarily affects Nextcloud Nextcloud Server. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2025-59788?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2025-59788 have an EU (EUVD) identifier?: Yes. CVE-2025-59788 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-201255.
When was CVE-2025-59788 published?: CVE-2025-59788 was published on 2025-12-04 and last updated on 2026-06-17.

References

Affected products (2)

cpe:2.3:a:nextcloud:nextcloud_server:*:*:*:*:-:*:*:*
cpe:2.3:a:nextcloud:nextcloud_server:*:*:*:*:enterprise:*:*:*

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