How severe is CVE-2016-9464?

CVE-2016-9464 has a CVSS 3.x base score of 4.3, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability none.

Is CVE-2016-9464 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (73rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2016-9464?

CVE-2016-9464 primarily affects Nextcloud Nextcloud Server. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2016-9464?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2016-9464 published?

CVE-2016-9464 was published on 2017-03-28 and last updated on 2026-06-17.

CVE-2016-9464

CVE-2016-9464 is a medium-severity vulnerability in Nextcloud Nextcloud Server with a CVSS 3.x base score of 4.3. 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-285.

Key facts

Severity: Medium (CVSS 3.x base score 4.3)
CVSS v2: 4.0
EPSS exploit prediction: 2% (73rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-285
Affected product: Nextcloud Nextcloud Server
Published: 2017-03-28
Last modified: 2026-06-17

Description

Nextcloud Server before 9.0.54 and 10.0.0 suffers from an improper authorization check on removing shares. The Sharing Backend as implemented in Nextcloud does differentiate between shares to users and groups. In case of a received group share, users should be able to unshare the file to themselves but not to the whole group. The previous API implementation simply unshared the file to all users in the group.

Frequently asked questions

What is CVE-2016-9464?: Nextcloud Server before 9.0.54 and 10.0.0 suffers from an improper authorization check on removing shares. The Sharing Backend as implemented in Nextcloud does differentiate between shares to users and groups. In case of a received group share, users should be able to unshare the file to themselves but not to the whole group. The previous API implementation simply unshared the file to all users in the group.
How severe is CVE-2016-9464?: CVE-2016-9464 has a CVSS 3.x base score of 4.3, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability none.
Is CVE-2016-9464 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (73rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2016-9464?: CVE-2016-9464 primarily affects Nextcloud Nextcloud Server. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2016-9464?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2016-9464 published?: CVE-2016-9464 was published on 2017-03-28 and last updated on 2026-06-17.

References

Affected products (2)

cpe:2.3:a:nextcloud:nextcloud_server:*:*:*:*:*:*:*:*
cpe:2.3:a:nextcloud:nextcloud_server:10.0:rc1:*:*:*:*:*:*

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