A missing check in Nextcloud Server prior to 14.0.0 could give unauthorized access to the previews of single file password protected shares.

published 2018-10-30 8 y ago modified 2026-06-17 4 mo ago also EUVD-2018-8303

cvss: 5.3; version 3.0, NVD
cisa kev: Not listed; not in CISA's catalog
epss: 1.1%; EPSS 1.1% chance of exploitation in 30 days, percentile 65%
public exploits: 0; none known

Patch / fix

fixed in 1

nextcloud nextcloud_server 14.0.0

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2018-16467 updated 2025-11-21 cvss 4.8

nextcloud: Improper access control checks for single share previews

Red Hat All currently supported Red Hat products
not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

Exploit prediction

1.07% chance of exploitation in the next 30 days, higher than 65% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

hackerone.com https://hackerone.com/reports/231917 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by	version	score	vector
NVD	3.0	5.3	CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
NVD	2.0	5.0	AV:N/AC:L/Au:N/C:P/I:N/A:N

Affected products

n/a Nextcloud Server

Classification

Weakness

CWE-200 Exposure of Sensitive Information to an Unauthorized Actor
CWE-287 Improper Authentication

References

hackerone.com /reports/231917
exploit, third-party-advisory
nextcloud.com /security/advisory/?id=NC-SA-2018-014
vendor-advisory

Sources

CVE List CVE-2018-16467
NVD CVE-2018-16467

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary