CVE-2026-45286
Last modified
CVE-2026-45286 is a medium-severity vulnerability rated 4.3/10 on the CVSS scale. Nextcloud is an open source content collaboration platform. From versions 5.5.13 to before 5.5.17, and 6.2.0 to before 6.2.3, an authenticated user can enumerate users on the same Nextcloud instance by using the Calendar app's endpoint for suggesting attendees. EPSS estimates a 0.28% chance of exploitation in the next 30 days.
Description
Nextcloud is an open source content collaboration platform. From versions 5.5.13 to before 5.5.17, and 6.2.0 to before 6.2.3, an authenticated user can enumerate users on the same Nextcloud instance by using the Calendar app's endpoint for suggesting attendees. The sharing restrictions, applied to other endpoints, were not effective here. This issue has been patched in versions 5.5.17 and 6.2.3.
Metrics
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N
Weakness Enumeration
Affected Software
| Vendor | Product | Versions |
|---|---|---|
| Nextcloud | Calendar | >= 5.5.13, < 5.5.17 |
| Nextcloud | Calendar | >= 6.2.0, < 6.2.3 |
References
- https://github.com/nextcloud/calendar/issues/7971Exploit, Issue Tracking, Patch
- https://github.com/nextcloud/calendar/pull/8197Issue Tracking, Patch
- https://github.com/nextcloud/security-advisories/security/advisories/GHSA-r697-74m9-gvf2Mitigation, Vendor Advisory
- https://hackerone.com/reports/3540663Permissions Required
Timeline
- Published
- Last Modified
- Status
- Analyzed
Frequently Asked Questions
What is CVE-2026-45286?
How severe is CVE-2026-45286?
How do I fix CVE-2026-45286?
Are you affected by CVE-2026-45286?
Run a free Strix scan to check your systems for this vulnerability.
Scan your code nowSource: NVD / NIST