CVE Vulnerabilities

CVE-2020-8121

Exposure of Resource to Wrong Sphere

Published: Feb 04, 2020 | Modified: Feb 11, 2020
CVSS 3.x
8.1
HIGH
Source:
NVD
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N
CVSS 2.x
5.5 MEDIUM
AV:N/AC:L/Au:S/C:P/I:P/A:N
RedHat/V2
RedHat/V3
Ubuntu

A bug in Nextcloud Server 14.0.4 could expose more data in reshared link shares than intended by the sharer.

Weakness

The product exposes a resource to the wrong control sphere, providing unintended actors with inappropriate access to the resource.

Affected Software

Name Vendor Start Version End Version
Nextcloud_server Nextcloud * 13.0.9 (excluding)
Nextcloud_server Nextcloud 14.0.0 (including) 14.0.5 (excluding)
Nextcloud_server Nextcloud 14.0.6 (including) 15.0.0 (excluding)

Extended Description

Resources such as files and directories may be inadvertently exposed through mechanisms such as insecure permissions, or when a program accidentally operates on the wrong object. For example, a program may intend that private files can only be provided to a specific user. This effectively defines a control sphere that is intended to prevent attackers from accessing these private files. If the file permissions are insecure, then parties other than the user will be able to access those files. A separate control sphere might effectively require that the user can only access the private files, but not any other files on the system. If the program does not ensure that the user is only requesting private files, then the user might be able to access other files on the system. In either case, the end result is that a resource has been exposed to the wrong party.

References