CVE-2021-37631 - CVE House
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Status published Medium CVE-2021-37631

Circle can be accessed by non-Circle members in Nextcloud Deck

Vulnerability Description

Deck is an open source kanban style organization tool aimed at personal planning and project organization for teams integrated with Nextcloud. In affected versions the Deck application didn't properly check membership of users in a Circle. This allowed other users in the instance to gain access to boards that have been shared with a Circle, even if the user was not a member of the circle. It is recommended that Nextcloud Deck is upgraded to 1.5.1, 1.4.4 or 1.2.9. If you are unable to update it is advised to disable the Deck plugin.

Impact Analysis

Refer to official advisory for detailed impact metrics.

Remediation

Ensure systems are updated to the latest vendor-supplied patch levels.

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Credits & Attribution

No credits recorded in the NVD database.

References

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Affected Vendor

Affected Software

security-advisories
Vulnerable Versions:
< 1.2.9, >= 1.3.0, < 1.4.4, >= 1.5.0, < 1.5.1

Timeline

Official Publish: September 7th, 2021
Last Modified: August 4th, 2024
Added to House: July 21st, 2026

CVSS Vectors

V3: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N

Weaknesses (CWE)

CWE-639

MITRE ATT&CK TTPs

T1190 Exploit Public-Facing Application
Initial Access
T1078 Valid Accounts
Persistence
T1213 Data from Information Repositories
Collection
T1021 Remote Services
Lateral Movement
T1098 Account Manipulation
Privilege Escalation