Nextcloud Desktop up to 3.16.4 information exposure

CVSS Meta Temp Score
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CTI Interest Score
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2.5$0-$5k0.00

Summaryinfo

A vulnerability, which was classified as problematic, was found in Nextcloud Desktop up to 3.16.4. This vulnerability affects unknown code. Executing a manipulation can lead to information exposure. This vulnerability is handled as CVE-2025-66549. The attack can be executed remotely. There is not any exploit available. You should upgrade the affected component.

Detailsinfo

A vulnerability was found in Nextcloud Desktop up to 3.16.4. It has been declared as problematic. This vulnerability affects some unknown functionality. The manipulation with an unknown input leads to a information exposure vulnerability. The CWE definition for the vulnerability is CWE-209. The product generates an error message that includes sensitive information about its environment, users, or associated data. As an impact it is known to affect confidentiality. CVE summarizes:

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.

The advisory is available at github.com. This vulnerability was named CVE-2025-66549 since 12/04/2025. The exploitation appears to be easy. The attack can be initiated remotely. The exploitation needs additional levels of successful authentication. Successful exploitation requires user interaction by the victim. The technical details are unknown and an exploit is not available. This vulnerability is assigned to T1592 by the MITRE ATT&CK project.

The vulnerability scanner Nessus provides a plugin with the ID 277719 (Linux Distros Unpatched Vulnerability : CVE-2025-66549), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 3.16.5 eliminates this vulnerability. Applying the patch 36d6c234d42b06a6f2e9de3e413a5c3c625edad6 is able to eliminate this problem. The bugfix is ready for download at github.com. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the vulnerability database at Tenable (277719). If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

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Version

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 2.5
VulDB Meta Temp Score: 2.5

VulDB Base Score: 2.4
VulDB Temp Score: 2.3
VulDB Vector: 🔒
VulDB Reliability: 🔍

NVD Base Score: 2.7
NVD Vector: 🔒

CNA Base Score: 2.4
CNA Vector (GitHub_M): 🔒

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Information exposure
CWE: CWE-209 / CWE-200 / CWE-284
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Nessus ID: 277719
Nessus Name: Linux Distros Unpatched Vulnerability : CVE-2025-66549

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Desktop 3.16.5
Patch: 36d6c234d42b06a6f2e9de3e413a5c3c625edad6

Timelineinfo

12/04/2025 CVE reserved
12/06/2025 +2 days Advisory disclosed
12/06/2025 +0 days VulDB entry created
12/09/2025 +3 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: GHSA-h9xj-qh76-q3hw
Status: Confirmed

CVE: CVE-2025-66549 (🔒)
GCVE (CVE): GCVE-0-2025-66549
GCVE (VulDB): GCVE-100-334546

Entryinfo

Created: 12/06/2025 05:00
Updated: 12/09/2025 21:36
Changes: 12/06/2025 05:00 (66), 12/09/2025 15:48 (2), 12/09/2025 21:36 (11)
Complete: 🔍
Cache ID: 216::103

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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