CVE-2021-32688

Description

Nextcloud Server is a Nextcloud package that handles data storage. Nextcloud Server supports application specific tokens for authentication purposes. These tokens are supposed to be granted to a specific applications (e.g. DAV sync clients), and can also be configured by the user to not have any filesystem access. Due to a lacking permission check, the tokens were able to change their own permissions in versions prior to 19.0.13, 20.0.11, and 21.0.3. Thus fileystem limited tokens were able to grant themselves access to the filesystem. The issue is patched in versions 19.0.13, 20.0.11, and 21.0.3. There are no known workarounds aside from upgrading.

CvssV3 impact

BaseSeverity

HIGH

ConfidentialityImpact

HIGH

AttackComplexity

LOW

Scope

UNCHANGED

AttackVector

NETWORK

AvailabilityImpact

HIGH

IntegrityImpact

HIGH

PrivilegesRequired

LOW

BaseScore

8.8

VectorString

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Version

3.1

UserInteraction

NONE

CvssV2 impact

AccessComplexity

LOW

ConfidentialityImpact

PARTIAL

AvailabilityImpact

PARTIAL

IntegrityImpact

PARTIAL

BaseScore

7.5

VectorString

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

Version

2.0

AccessVector

NETWORK

Authentication

NONE