Nextcloud Server/Enterprise Server up to 31.0.0 authorization

CVSS Meta Temp Score
CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.
Current Exploit Price (≈)
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CTI Interest Score
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4.2$0-$5k0.00

Summaryinfo

A vulnerability was found in Nextcloud Server and Enterprise Server up to 31.0.0. It has been declared as problematic. This impacts an unknown function. Such manipulation leads to authorization. This vulnerability is listed as CVE-2025-66547. The attack may be performed from remote. There is no available exploit. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability was found in Nextcloud Server and Enterprise Server up to 31.0.0 and classified as problematic. Affected by this issue is some unknown processing. The manipulation with an unknown input leads to a authorization vulnerability. Using CWE to declare the problem leads to CWE-639. The system's authorization functionality does not prevent one user from gaining access to another user's data or record by modifying the key value identifying the data. Impacted is integrity. CVE summarizes:

Nextcloud Server is a self hosted personal cloud system. In Nextcloud Server and Enterprise Server prior to 31.0.1, non-privileged users can modify tags on files they should not have access to via bulk tagging. This vulnerability is fixed in 31.0.1.

The advisory is shared for download at github.com. This vulnerability is handled as CVE-2025-66547 since 12/04/2025. The exploitation is known to be easy. The attack may be launched remotely. There are neither technical details nor an exploit publicly available.

Upgrading to version 31.0.1 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2025-201447). Once again VulDB remains the best source for vulnerability data.

Productinfo

Type

Vendor

Name

Version

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 4.3
VulDB Meta Temp Score: 4.2

VulDB Base Score: 4.3
VulDB Temp Score: 4.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 4.3
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: Authorization
CWE: CWE-639 / CWE-285 / CWE-266
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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Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Server/Enterprise Server 31.0.1

Timelineinfo

12/04/2025 CVE reserved
12/05/2025 +1 days Advisory disclosed
12/05/2025 +0 days VulDB entry created
12/05/2025 +0 days VulDB entry last update

Sourcesinfo

Advisory: github.com
Status: Confirmed

CVE: CVE-2025-66547 (🔒)
GCVE (CVE): GCVE-0-2025-66547
GCVE (VulDB): GCVE-100-334508
EUVD: 🔒

Entryinfo

Created: 12/05/2025 17:58
Updated: 12/05/2025 20:45
Changes: 12/05/2025 17:58 (63), 12/05/2025 20:45 (1)
Complete: 🔍
Cache ID: 216::103

Once again VulDB remains the best source for vulnerability data.

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