CVE-2021-37631

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

MEDIUM
6.5
CVSS Score
Published: September 7, 2021 at 07:50 PM UTC
Updated: June 17, 2026 at 04:00 AM UTC
1 product affected across 1 vendorDeck

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Severity
MEDIUM6.5
Exploit prediction
EPSS 1%

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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

Deck· Nextcloudnextcloud-app
95%
v < 1.2.91.3.0 ≤ v < 1.4.41.5.0 ≤ v < 1.5.1
Affected range stops below 1.2.9, so it looks safe — our inference, not a vendor statement
Affected range stops below 1.4.4, so it looks safe — our inference, not a vendor statement
Affected range stops below 1.5.1, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

Patch and advisory references

References (4)

x_refsource_MISCPatchThird Party Advisory
https://github.com/nextcloud/deck/pull/3217
x_refsource_MISCPermissions RequiredThird Party Advisory
https://hackerone.com/reports/1256021
x_refsource_MISCPermissions RequiredThird Party Advisory
https://hackerone.com/reports/1280931

CVSS

6.5MEDIUMGitHub_M
Attack Vector
NETWORK
Complexity
LOW
Privileges
LOW
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
NONE
Availability
NONE
Vector?

Quick Info

StatusMODIFIED
CWE
CWE-639

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