Vulnerability in Nextcloud Security-Advisories
CVE-2026-45284
Nextcloud is an open source content collaboration platform. From version 1.3.6 to before version 8.4.0, an improper check allowed users that where provided by LDAP to still authenticate towards user OIDC after they where deleted. This issue has been patched in version 8.4.0.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 4.6 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:L/I:L/A:L.
EPSS exploit prediction
EPSS: 0.004 (27.6th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 28th percentile — 27.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.002 · newest: 0.004 · change: +0.002
Affected products
- Nextcloud Security-Advisories — versions >= 1.3.6, < 8.4.0
- Nextcloud User Oidc
Weakness classification (CWE)
References
- github.com/nextcloud/security-advisories/security/advisories/GHSA-79xf-ffj8-96fm (Mitigation, Vendor Advisory)
- github.com/nextcloud/user_oidc/pull/1340 (Patch, Issue Tracking)
- hackerone.com/reports/3554696 (Permissions Required)
Frequently asked questions
- What is CVE-2026-45284?
- CVE-2026-45284 is a medium-severity vulnerability in Nextcloud Security-Advisories, classified under Improper Access Control. CVSS score: 4.6/10. Published 2026-06-01.
- How severe is CVE-2026-45284?
- Medium severity. CVSS v3 base score is 4.6 out of 10.