Read the docs
TI-2026-81400 Aliases CVE-2026-82984

Missing access control in Nextcloud Server exposes team resources

Priority LOW 20CWE-284Published · Updated

Key facts

Attack vector
Network
Privileges required
Low
User interaction
None
Attack complexity
Low
Impact type
Security bypass
Confidentiality · integrity · availability
Low · None · None
Fix status
No fix listed

Attack profile from CVSS 3.0 · CNA. Fix status from CNA. Impact type from CWE-284.

Summary

Nextcloud Server from 32.0.0 through 33.0.0 is affected. For teams set to visible to everyone, the web UI blocks non-members, but the resources API endpoint does not enforce the same check. This is CWE-284, an improper access control flaw. Any authenticated non-member can list the team's internal resources and their identifiers, though not the contents of those resources.

Written with Claude Haiku 5.5 from the sources below · 2026-11-04

Description from the CNA

When a team was configured as "visible to everyone", the web UI correctly blocked non-members from viewing the team ("You are not a member of ..."), but the resources API endpoint could still be called directly, allowing any authenticated non-member to enumerate the team's internal resources and their identifiers. This does not grant access to the contents of the discovered resources themselves, only their existence, names, and identifiers.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00274 19th percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet

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
nextcloudServer32.0.0 – 33.0.0—No fix listedCNA
  • Server Vendornextcloud Affected 32.0.0 – 33.0.0 Fixed in — No fix listed CNA

Remediation

The sources list no fixed version for Nextcloud Server.

Written with Claude Haiku 5.5 from the sources below · 2026-11-04

Timeline

  1. 2026-10-27 Threatist record created from CVE-2026-82984
  2. 2026-11-04 CISA SSVC decision points changed

References

Other 1

  • 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