CVE-2025-66554

Description

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 v3.1 Score

3.5

LOW

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

Weakness Type (CWE)

CWE-79 Cross-site Scripting (XSS)

Affected Products

Vendor	Product	Versions
nextcloud	contacts	5.0.0 — 5.5.4
nextcloud	contacts	6.0.0 — 6.0.6
nextcloud	contacts	7.0.0 — 7.2.5

References

Advisories & Patches

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

Frequently Asked Questions

What is 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 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. It has a CVSS v3.1 base score of 3.5 (LOW).

How severe is CVE-2025-66554? +

CVE-2025-66554 has a CVSS v3.1 score of 3.5 out of 10, rated LOW. This is a low-severity vulnerability with limited impact.

What products are affected by CVE-2025-66554? +

CVE-2025-66554 affects products from nextcloud, specifically: contacts. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2025-66554? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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