Vulnerability Report

CVE-2025-66549

Title: Nextcloud Desktop Sync Client Path Leak

Information Disclosure

Proof Of Concept

No public PoC currently indexed for CVE-2025-66549.

CWE Category CWE-209
Published Date Dec 05, 2025
Modified Date Dec 09, 2025
Exploit Status Not Found
Score 2.4 CVSS v3.1
Exploit Probability (EPSS)
0.24%

Vulnerability Summary

CVE-2025-66549: 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.

Impacted Vendors

A
avira 1
N
nextcloud 1

Reference Links

https://github.com/nextcloud/desktop/commit/36d6c234d42b06a6f2e9de3e413a5c3c625edad6 https://github.com/nextcloud/desktop/pull/8330 https://github.com/nextcloud/security-advisories/security/advisories/GHSA-h9xj-qh76-q3hw https://hackerone.com/reports/3159877
CVSS v3.1
Source Entity [email protected]
Severity LOW
2.7
Attack Vector
NETWORK
Complexity
LOW
Privileges
N/A
Interaction
NONE
Confidentiality
N/A
Integrity
N/A
Availability
N/A
Scope
UNCHANGED
RAW VECTOR CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:L/I:N/A:N
CVSS v3.1
Source Entity [email protected]
Severity LOW
2.4
Attack Vector
NETWORK
Complexity
LOW
Privileges
N/A
Interaction
REQUIRED
Confidentiality
N/A
Integrity
N/A
Availability
N/A
Scope
UNCHANGED
RAW VECTOR CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:U/C:L/I:N/A:N

Associated Attack Patterns (CAPEC)

Total: Patterns

CVE-2025-66549 Exploits & PoCs (Proof Of Concept)

No public PoCs found in our database for this CVE.

MODIFIED

Vulnerability data or affected products updated.

MODIFIED

Vulnerability data updated via NVD.

PUBLISHED

Vulnerability first announced in NVD.

Attack Vector Matrix

Access Vector NETWORK
Complexity LOW
Privileges N/A
Interaction NONE
CVSS Vector String CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:L/I:N/A:N

Affected Stack

No specific products linked.