What is CVE-2018-16464?

CVE-2018-16464 is a medium-severity vulnerability in Nextcloud Server, classified under Improper Authentication. CVSS score: 5.7/10. Published 2018-10-30.

How severe is CVE-2018-16464?

Medium severity. CVSS v3 base score is 5.7 out of 10.

Auth bypass in Nextcloud Server

CVE-2018-16464

A missing access check in Nextcloud Server prior to 14.0.0 could lead to continued access to password protected link shares when the owner had changed the password.

Vulnerability class: Broken Authentication

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

CVSS v3 metric

CVSS v3 base score 5.7 (Medium). Vector: CVSS:3.0/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:N/A:N.

EPSS exploit prediction

EPSS: 0.009 (57.8th percentile), scored 2026-09-29.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 58th percentile — 57.8% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.009 · newest: 0.009 · change: 0.000

Affected products

Nextcloud Server
Nextcloud Server — versions <14.0.0

Weakness classification (CWE)

CWE-287 — Improper Authentication

References

hackerone.com/reports/146133 (Third Party Advisory)
nextcloud.com/security/advisory/ (Vendor Advisory)

Frequently asked questions

What is CVE-2018-16464?: CVE-2018-16464 is a medium-severity vulnerability in Nextcloud Server, classified under Improper Authentication. CVSS score: 5.7/10. Published 2018-10-30.
How severe is CVE-2018-16464?: Medium severity. CVSS v3 base score is 5.7 out of 10.