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TI-2026-32983 Aliases CVE-2026-45155

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

Priority LOW 13CWE-639Published · Updated

Key facts

Attack vector
Network
Privileges required
Low
User interaction
Required
Attack complexity
High
Impact type
Security bypass
Confidentiality · integrity · availability
Low · None · None
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-639.

Summary

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

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.002 9th percentileScored 2026-11-07
Fix Fixed security-advisories (nextcloud): 32.0.7, 33.0.1

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
nextcloudsecurity-advisories32.0.0 to before 32.0.7; 33.0.0 to before 33.0.132.0.7, 33.0.1Patch availableCNA
  • security-advisories Vendornextcloud Affected 32.0.0 to before 32.0.7; 33.0.0 to before 33.0.1 Fixed in 32.0.7, 33.0.1 Patch available CNA

Remediation

  • Fix · CNA security-advisories (nextcloud) Fixed in 32.0.7, 33.0.1

Vendor assessments

Red Hat

Red Hat's page for this CVE →

Not affected: 1 product
  • Red Hat

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-45155

References

Other 3

  • TI-2026-18211 Windmill < 1.615.0 Operator Role Missing Authorization Checks RCE CVSS 4.0HIGH 8.7
  • TI-2023-14838 NextCloud Cookbook's pull-checks.yml workflow is vulnerable to OS Command Injection CVSS 3.1HIGH 8.8
  • TI-2022-08650 Command Injection in Appointment Emails for Nextcloud Calendar CVSS 3.1CRITICAL 9.8
  • TI-2023-20855 Users can delete external storage mount points CVSS 3.1HIGH 7.7
  • TI-2023-11091 Nextcloud download permissions can be changed by resharer CVSS 3.1HIGH 7.5
  • TI-2023-10624 Nextcloud Server vulnerable to SSRF via filter bypass due to lax checking on IPs CVSS 3.1MEDIUM 5.3
See all 401 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences