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TI-2025-40960 Aliases CVE-2025-66549

Nextcloud Desktop discloses information when attempting to lock a file inside a end-to-end encrypted directory

Priority LOW 14CWE-209Published · Updated

Key facts

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

Attack profile from CVSS 3.1 · NVD. Fix status from CNA. Impact type from CWE-209.

Summary

Nextcloud Desktop is the desktop sync client for Nextcloud. Prior to 3.16.5, when trying to manually lock a file inside an end-to-end encrypted directory, the path of the file was sent to the server unencrypted, making it possible for administrators to see it in log files. This vulnerability is fixed in 3.16.5.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00318 24th percentileScored 2026-11-07
Fix Fixed security-advisories (nextcloud): 3.16.5

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 3.16.53.16.5Patch availableCNA
  • security-advisories Vendornextcloud Affected before 3.16.5 Fixed in 3.16.5 Patch available CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:nextcloud:desktop:*:*:*:*:*:*:*:*3.0.0 to before 3.16.5Vulnerablenextcloud
  • cpe:2.3:a:nextcloud:desktop:*:*:*:*:*:*:*:* Versions 3.0.0 to before 3.16.5 Vulnerable ·nextcloud

Remediation

  • Fix · CNA security-advisories (nextcloud) Fixed in 3.16.5

Timeline

  1. 2026-10-02 Threatist record created from CVE-2025-66549

References

Patch 2

Advisory 1

Other 1

  • TI-2022-18709 Cross-site scripting (XSS) in Nextcloud Desktop Client CVSS 3.1MEDIUM 6.1
  • TI-2022-18708 Cross-site scripting (XSS) in Nextcloud Desktop Client CVSS 3.1MEDIUM 5.4
  • TI-2022-18707 Cross-site Scripting (XSS) in Nexcloud Desktop Client CVSS 3.1MEDIUM 5.4
  • TI-2022-18710 nextcloudcmd incorrectly trusts bad TLS certificates CVSS 3.1MEDIUM 4.7
  • TI-2020-06645 Path traversal in Desktop Client CVSS 3.1MEDIUM 6.8
  • TI-2021-05740 Injection in Nextcloud Desktop Client CVSS 3.1HIGH 8.8
See all 26 →

Sources

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