CVE-2026-45155

LOW

Nextcloud: Private circle can be added to another circle via API

Title source: cna
STIX 2.1

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

References (3)

Core 3
Core References
X_Refsource_Misc x_refsource_misc
https://github.com/nextcloud/circles/pull/2401
X_Refsource_Misc x_refsource_misc
https://hackerone.com/reports/3511998

Scores

CVSS v3 2.6
EPSS 0.0020
EPSS Percentile 9.9%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:L/I:N/A:N

Details

CWE
CWE-639
Status published
Products (2)
nextcloud/security-advisories >= 32.0.0, < 32.0.7
nextcloud/security-advisories >= 33.0.0, < 33.0.1
Published Jun 01, 2026
Tracked Since Jun 01, 2026