CVE-2021-32656

Nextcloud Server is a Nextcloud package that handles data storage. A vulnerability in federated share exists in versions prior to 19.0.11, 20.0.10, and 21.0.2. An attacker can gain access to basic information about users of a server by accessing a public link that a legitimate server user added as a federated share. This happens because Nextcloud supports sharing registered users with other Nextcloud servers, which can be done automatically when selecting the "Add server automatically once a federated share was created successfully" setting. The vulnerability is patched in versions 19.0.11, 20.0.10, and 21.0.2 As a workaround, disable "Add server automatically once a federated share was created successfully" in the Nextcloud settings.

CVSS v3.0 8.6 HIGH
CVSS v2.0 5.0 MEDIUM

8.6^/10

CVSS v3.0 : HIGH

Vector :

Exploitability : 3.9 / Impact : 4.0

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope CHANGED

5.0^/10

CVSS v2.0 : MEDIUM

Vector : AV:N/AC:L/Au:N/C:P/I:N/A:N

Exploitability : 10.0 / Impact : 2.9

Access Vector NETWORK

Access Complexity LOW

Authentication NONE

Confidentiality Impact PARTIAL

Integrity Impact NONE

Availability Impact NONE

References

Link	Resource
https://hackerone.com/reports/1167853	Permissions Required Third Party Advisory
https://github.com/nextcloud/security-advisories/security/advisories/GHSA-j875-vr2q-h6x6	Third Party Advisory
https://security.gentoo.org/glsa/202208-17	Third Party Advisory

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Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:nextcloud:nextcloud_server::::::::
	cpe:2.3:a:nextcloud:nextcloud_server::::::::
	cpe:2.3:a:nextcloud:nextcloud_server::::::::

Information

Published : 2021-06-01 15:15

Updated : 2022-10-25 08:47

NVD link : CVE-2021-32656

Mitre link : CVE-2021-32656

JSON object : View

CWE

CWE-284

Improper Access Control

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Products Affected

nextcloud

nextcloud_server

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