CVE-2025-66554

Nextcloud Contacts vulnerable to Stored XSS in contacts app via organisation and title field

CVSS 3.5 LOWEPSS 0.2%CWE-79

Vexday Risk Score

8Low

SSVC decision (CISA)

Track

No exploitation signal → monitor

CVSS 3.5EPSS 0.2%KEV nãoPoC —Nuclei —Metasploit —Patch —

Lifecycle

05 Dec 2025Published on NVD

Recommendation: Monitor — no exploitation signal at the moment.

Contacts app for Nextcloud easily syncs contacts from various devices with your Nextcloud and allows editing. Prior to 5.5.4, 6.0.6, and 7.2.5, a malicious user was able to modify their organisation and title field to load additional CSS files. Javascript and other options were correctly blocked by the content security policy of the Nextcloud Server code. This vulnerability is fixed in 5.5.4, 6.0.6, and 7.2.5.

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

Affected products

nextcloud · security-advisories

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References

https://github.com/nextcloud/contacts/commit/d954d098978dde1f121600e8b994e02f293c68b1 https://github.com/nextcloud/contacts/pull/4619 https://github.com/nextcloud/security-advisories/security/advisories/GHSA-9v78-cpfc-v6h2 https://hackerone.com/reports/3293290