CVE-2025-66512

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.
Basic XSS
ProviderTypeBase ScoreAtk. VectorAtk. ComplexityPriv. RequiredVector
NISTNIST
5.4 MEDIUM
NETWORK
LOW
NONE
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:L
GitHub_MCNA
5.4 MEDIUM
NETWORK
LOW
NONE
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:L
CISA-ADPADP
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Awaiting analysis
This vulnerability is currently awaiting analysis.
Base Score
CVSS 3.x
EPSS Score
Percentile: Unknown
Common Weakness Enumeration
Vulnerability Media Exposure
References
https://github.com/nextcloud/security-advisories/security/advisories/GHSA-qcw2-p26m-9gc5
https://github.com/nextcloud/viewer/commit/5044a27d61bc40c0f134298d36af91f865335b63
https://github.com/nextcloud/viewer/pull/3023
https://hackerone.com/reports/3357808