Auth bypass in Nextcloud Deck
CVE-2021-37631
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.
Vulnerability class: IDOR (Insecure Direct Object Reference)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N.
EPSS exploit prediction
EPSS: 0.013 (68.8th percentile), scored .
Low probability of exploitation in the next 30 days, but still tracked. 69th percentile — 68.8% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.013 · newest: 0.013 · change: 0.000
Affected products
- Nextcloud Deck
- Nextcloud Security-Advisories — versions < 1.2.9, >= 1.3.0, < 1.4.4, >= 1.5.0, < 1.5.1
Weakness classification (CWE)
References
- github.com/nextcloud/security-advisories/security/advisories/GHSA-4mxp-j277-82hr (Third Party Advisory)
- github.com/nextcloud/deck/pull/3217 (Patch, Third Party Advisory)
- hackerone.com/reports/1256021 (Permissions Required, Third Party Advisory)
- hackerone.com/reports/1280931 (Permissions Required, Third Party Advisory)
Frequently asked questions
- What is CVE-2021-37631?
- CVE-2021-37631 is a medium-severity vulnerability in Nextcloud Deck, classified under Authorization Bypass Through User-Controlled Key. CVSS score: 6.5/10. Published 2021-09-07.
- How severe is CVE-2021-37631?
- Medium severity. CVSS v3 base score is 6.5 out of 10.