CVE-2026-45286
Nextcloud: Calendar app leaked user identifiers via attendee suggestion endpoint
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.
No summary for this CVE yet.
CVSS Vector Breakdown
Exploitability
AV:NAttack VectorNetwork
AC:LAttack ComplexityLow
PR:LPrivileges RequiredLow
UI:NUser InteractionNone
Scope
S:UScopeUnchanged
Impact
C:LConfidentialityLow
I:NIntegrityNone
A:NAvailabilityNone
Weaknesses
Affected Products
nextcloud
oss-project·DEaka nextcloud server
Exploitability
Official Patch Available
Workaround Available
Attack Graph
Products CVE Techniques Tactics
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MITRE ATT&CK
1 technique Collection
References
https://github.com/nextcloud/calendar/issues/7971
github.com
https://github.com/nextcloud/calendar/pull/8197
github.com
https://github.com/nextcloud/security-advisories/security/advisories/GHSA-r697-74m9-gvf2
github.com
and 1 more references View all →
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