Nextcloud: Private circle can be added to another circle via API
Summary
| CVE | CVE-2026-45155 |
|---|---|
| State | PUBLISHED |
| Assigner | GitHub_M |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-06-01 17:17:09 UTC |
| Updated | 2026-06-01 18:14:29 UTC |
| Description | Nextcloud is an open source content collaboration platform. In Nextcloud Server from versions 32.0.0 to before 32.0.7 and 33.0.0 to before 33.0.1, a missing access check on API level allowed to add unknown circles by their ID directly to other circles. Since circle IDs have 62^15 complexity by default this is still unlikely to be executable at will, but if access to an ID was available via another source, memberships could be tracked like this. It is recommended that the Nextcloud Server is upgraded to 32.0.7 or 33.0.1. It is recommended that the Nextcloud Enterprise Server is upgraded to 29.0.16.14, 30.0.17.8, 31.0.14.3, 32.0.7 or 33.0.1 |
Risk And Classification
Primary CVSS: v3.1 2.6 LOW from [email protected]
CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:L/I:N/A:N
EPSS: 0.000250000 probability, percentile 0.074600000 (date 2026-06-02)
Problem Types: CWE-639 | CWE-639 CWE-639: Authorization Bypass Through User-Controlled Key
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 3.1 | [email protected] | Secondary | 2.6 | LOW | CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:L/I:N/A:N |
| 3.1 | CNA | DECLARED | 2.6 | LOW | CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:L/I:N/A:N |
CVSS v3.1 Breakdown
Attack Vector
NetworkAttack Complexity
HighPrivileges Required
LowUser Interaction
RequiredScope
UnchangedConfidentiality
LowIntegrity
NoneAvailability
NoneCVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:L/I:N/A:N
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | Nextcloud | Security-advisories | affected >= 32.0.0, < 32.0.7 | Not specified |
| CNA | Nextcloud | Security-advisories | affected >= 33.0.0, < 33.0.1 | Not specified |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| github.com/nextcloud/circles/pull/2401 | [email protected] | github.com | |
| github.com/nextcloud/security-advisories/security/advisories/GHSA-xpgv-g... | [email protected] | github.com | |
| hackerone.com/reports/3511998 | [email protected] | hackerone.com | |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
No vendor comments have been submitted for this CVE.
There are currently no legacy QID mappings associated with this CVE.