CVE-2025-66512

MEDIUM EPSS 14.1%
Published Dec 5, 20257mo ago · Modified Jun 17, 20262w ago
6.1 CVSS 3.1
Medium
Find Similar
Published Dec 5, 2025 7mo ago
Last Modified Jun 17, 2026 2w ago

Description

Nextcloud Server is a self hosted personal cloud system. In Nextcloud Server and Server Enterprise prior to 31.0.12 and 32.0.3, a missing sanitization allowed malicious users to circumvent the content security policy when a malicious user manages to trick a user it viewing an uploaded SVG outside of the Nextcloud Servers web page.

CVSS Details

Base Score
6.1
Exploitability
2.8
Impact
2.7
Vector string
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
Attack Vector Network
Attack Complexity Low
Privileges Required None
User Interaction Required
Scope Changed
Confidentiality Low
Integrity Low
Availability None

Threat Intelligence

EPSS Exploit Probability
14.1% percentile
Exploit & Patch Status
No Known Exploit
Patch Available

Weaknesses 2

CWE-79 Cross-site Scripting Injection
CWE-80

Affected Products 4

VendorProductVersionRange
nextcloudnextcloud_server*≥31.0.0  –  <31.0.12
nextcloudnextcloud_server*≥31.0.0  –  <31.0.12
nextcloudnextcloud_server*≥32.0.0  –  <32.0.3
nextcloudnextcloud_server*≥32.0.0  –  <32.0.3

References 4

  • github.com https://github.com/nextcloud/security-advisories/security/advisories/GHSA-qcw2-p26m-9gc5
    PatchVendor Advisory
  • github.com https://github.com/nextcloud/viewer/commit/5044a27d61bc40c0f134298d36af91f865335b63
    Patch
  • github.com https://github.com/nextcloud/viewer/pull/3023
    Issue Tracking
  • hackerone.com https://hackerone.com/reports/3357808
    Issue TrackingVendor Advisory

Remediation

  • github.com https://github.com/nextcloud/security-advisories/security/advisories/GHSA-qcw2-p26m-9gc5
    PatchVendor Advisory
  • github.com https://github.com/nextcloud/viewer/commit/5044a27d61bc40c0f134298d36af91f865335b63
    Patch