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TI-2021-18005 Aliases CVE-2021-41166

Permission bypass in Nextcloud Android App

Priority LOW 26CWE-276Published · Updated

Key facts

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

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

Summary

The Nextcloud Android app is the Android client for Nextcloud, a self-hosted productivity platform. An issue in versions prior to 3.17.1 may lead to sensitive information disclosure. An unauthorized app that does not have the otherwise required `MANAGE_DOCUMENTS` permission may view image thumbnails for images it does not have permission to view. Version 3.17.1 contains a patch. There are no known workarounds.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00948 61st percentileScored 2026-11-07
Fix Fixed security-advisories (nextcloud): 3.17.1

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-advisoriesbefore 3.17.13.17.1Patch availableCNA
  • security-advisories Vendornextcloud Affected before 3.17.1 Fixed in 3.17.1 Patch available CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:nextcloud:nextcloud:*:*:*:*:*:android:*:*before 3.17.1Vulnerablenextcloud
  • cpe:2.3:a:nextcloud:nextcloud:*:*:*:*:*:android:*:* Versions before 3.17.1 Vulnerable ·nextcloud

Remediation

  • Fix · CNA security-advisories (nextcloud) Fixed in 3.17.1

Timeline

  1. 2026-10-02 Threatist record created from CVE-2021-41166

References

Patch 3

Other 1

  • TI-2022-11704 Sensitive files/data exist after deletion of user account in Nextcloud Android CVSS 3.1LOW 3.3
  • TI-2022-08695 Improper Authentication in Nextcloud Android Files CVSS 3.1LOW 2.4
  • TI-2019-03862 SQL injection in com.nextcloud.client CVSS 3.1CRITICAL 9.8
  • TI-2021-19669 SQL Injection in FileContentProvider (GHSL-2021-1007) CVSS 3.1HIGH 7.5
  • TI-2023-13460 Nextcloud: Lack of authenticity of metadata keys allows a malicious server to gain access to E2EE folders CVSS 3.1MEDIUM 6.9
  • TI-2021-12395 End-to-end encryption device setup did not verify public key CVSS 3.1HIGH 7.5
See all 27 →

Sources

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