What is CVE-2018-16466?

CVE-2018-16466 is a high-severity vulnerability in Nextcloud Server, classified under Improper Access Control. CVSS score: 8.1/10. Published 2018-10-30.

How severe is CVE-2018-16466?

High severity. CVSS v3 base score is 8.1 out of 10.

Vulnerability in Nextcloud Server

CVE-2018-16466

Improper revalidation of permissions in Nextcloud Server prior to 14.0.0, 13.0.6 and 12.0.11 lead to not accepting access restrictions by acess tokens.

Published 2018-10-30 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 8.1 (High). Vector: CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N.

EPSS exploit prediction

EPSS: 0.010 (60.8th percentile), scored 2026-10-19.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 61st percentile — 60.8% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.010 · newest: 0.010 · change: 0.000

Affected products

Nextcloud Server — versions 14.0.0
Nextcloud Server — versions <14.0.0, <13.0.6, <12.0.11

Weakness classification (CWE)

References

hackerone.com/reports/388515 (Third Party Advisory)
nextcloud.com/security/advisory/ (Vendor Advisory)

Frequently asked questions

What is CVE-2018-16466?: CVE-2018-16466 is a high-severity vulnerability in Nextcloud Server, classified under Improper Access Control. CVSS score: 8.1/10. Published 2018-10-30.
How severe is CVE-2018-16466?: High severity. CVSS v3 base score is 8.1 out of 10.