CVE-2016-9464: nextcloud nextcloud_server Improper Authorization
Vulnerability summary
CVE-2016-9464 is a medium (CVSS 4.3) Improper Authorization vulnerability in nextcloud nextcloud_server. EPSS estimates a 1.62% chance of exploitation in the next 30 days, higher than 75.7% of scored vulnerabilities. 1 public exploit is recorded.
Timeline
- 28-03-2017PublishedVulnerability first disclosed.
- 06-08-2024Last modifiedVulnerability information updated.
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.
CVSS metrics
2 scores · 1 source · 2 versionsEPSS trend
Probability
1.62%
Chance of exploitation in the next 30 days
Percentile
76%
Versus all other CVEs
30-day change
0.00 pp
From 1.62% on 18-09-2026
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
1 foundExploit Reference (hackerone.com)
Maturity: unknown
Weaknesses
CWE · root causeAffected systems
Nextcloud1 product
- nextcloud_serverEOL< 9.0.54 | 10.0:rc1
1 vendor · 1 product
References
7 links- github.com/nextcloud/server/commit/7289cb5ec0b812992ab0dfb889744b94bc0994f0X Refsource MISCIssue TrackingPatchThird Party Advisory
- github.com/nextcloud/server/commit/3387e5d00fcf6b2ea6b285a091e5743f545e7202X Refsource MISCIssue TrackingPatchThird Party Advisory
- github.com/nextcloud/server/commit/a5471b4a3e3f30e99e4de39c97c0c3b3c2f1618fX Refsource MISCIssue TrackingPatchThird Party Advisory
- github.com/nextcloud/server/commit/e2c4f4f9aa11bc92e8f2212cce73841b922187e8X Refsource MISCIssue TrackingPatchThird Party Advisory