CVE-2025-66554: 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…

PriorityP428medium5.4CVSS 3.1

AVNACLPRLUIRSCCLILAN

EPSS

0.20%

10.4th percentile

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.

Affected

6 ranges

Vendor	Product	Version range	Fixed in
nextcloud	contacts	>= 5.0.0 < 5.5.4	5.5.4
nextcloud	contacts	>= 6.0.0 < 6.0.6	6.0.6
nextcloud	contacts	>= 7.0.0 < 7.2.5	7.2.5
nextcloud	security-advisories	< 5.5.4	5.5.4
nextcloud	security-advisories	—	—
nextcloud	security-advisories	—	—

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