How severe is CVE-2018-16466?

CVE-2018-16466 has a CVSS 3.x base score of 8.1, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability none.

Is CVE-2018-16466 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (57th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-16466?

CVE-2018-16466 primarily affects Nextcloud Nextcloud Server. In total, 7 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2018-16466?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2018-16466 published?

CVE-2018-16466 was published on 2018-10-30 and last updated on 2026-06-17.

CVE-2018-16466

CVE-2018-16466 is a high-severity vulnerability in Nextcloud Nextcloud Server with a CVSS 3.x base score of 8.1. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-273.

Key facts

Severity: High (CVSS 3.x base score 8.1)
CVSS v2: 5.5
EPSS exploit prediction: 1% (57th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-273
Affected product: Nextcloud Nextcloud Server
Published: 2018-10-30
Last modified: 2026-06-17

Description

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.

Frequently asked questions

What is 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.
How severe is CVE-2018-16466?: CVE-2018-16466 has a CVSS 3.x base score of 8.1, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability none.
Is CVE-2018-16466 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (57th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-16466?: CVE-2018-16466 primarily affects Nextcloud Nextcloud Server. In total, 7 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2018-16466?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2018-16466 published?: CVE-2018-16466 was published on 2018-10-30 and last updated on 2026-06-17.

References

Affected products (7)

cpe:2.3:a:nextcloud:nextcloud_server:*:*:*:*:*:*:*:*
cpe:2.3:a:nextcloud:nextcloud_server:14.0.0:beta1:*:*:*:*:*:*
cpe:2.3:a:nextcloud:nextcloud_server:14.0.0:beta2:*:*:*:*:*:*
cpe:2.3:a:nextcloud:nextcloud_server:14.0.0:beta3:*:*:*:*:*:*
cpe:2.3:a:nextcloud:nextcloud_server:14.0.0:beta4:*:*:*:*:*:*
cpe:2.3:a:nextcloud:nextcloud_server:14.0.0:rc1:*:*:*:*:*:*
cpe:2.3:a:nextcloud:nextcloud_server:14.0.0:rc2:*:*:*:*:*:*

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