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TI-2021-12323 Aliases CVE-2021-32655

Files Drop public link can be added as federated share

Priority LOW 19CWE-241Published · Updated

Key facts

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

Attack profile from CVSS 3.1 · CNA. Fix status from CNA.

Summary

Nextcloud Server is a Nextcloud package that handles data storage. In versions prior to 19.0.11, 20.0.10, and 21.0.2, an attacker is able to convert a Files Drop link to a federated share. This causes an issue on the UI side of the sharing user. When the sharing user opens the sharing panel and tries to remove the "Create" privileges of this unexpected share, Nextcloud server would silently grant the share read privileges. The vulnerability is patched in versions 19.0.11, 20.0.10 and 21.0.2. No workarounds are known to exist.

Why it matters now

EPSS 0.01034 64th percentileScored 2026-11-07
Fix Fixed security-advisories (nextcloud): 19.0.11, 20.0.10, 21.0.2

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
nextcloudsecurity-advisoriesbefore 19.0.11; 20.0.0 to before 20.0.10; 21.0.0 to before 21.0.219.0.11, 20.0.10, 21.0.2Patch availableCNA
  • security-advisories Vendornextcloud Affected before 19.0.11; 20.0.0 to before 20.0.10; 21.0.0 to before 21.0.2 Fixed in 19.0.11, 20.0.10, 21.0.2 Patch available CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:nextcloud:nextcloud_server:*:*:*:*:*:*:*:*before 19.0.11; 20.0.0 to before 20.0.10; 21.0.0 to before 21.0.2Vulnerablenextcloud
  • cpe:2.3:a:nextcloud:nextcloud_server:*:*:*:*:*:*:*:* Versions before 19.0.11; 20.0.0 to before 20.0.10; 21.0.0 to before 21.0.2 Vulnerable ·nextcloud

Remediation

  • Fix · CNA security-advisories (nextcloud) Fixed in 19.0.11, 20.0.10, 21.0.2

Timeline

  1. 2026-10-02 Threatist record created from CVE-2021-32655

References

Advisory 3

  • 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
  • TI-2025-37238 Cross-site scripting in Nextcloud CVSS 3.1MEDIUM 6.4
  • TI-2023-11086 nextcloud vulnerable to Uncontrolled Resource Consumption CVSS 3.1MEDIUM 6.5
  • TI-2022-18738 Exception logging in Sharepoint app reveals clear-text connection details CVSS 3.1MEDIUM 6.5
See all 188 →

Sources

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