CVE-2021-32656
A vulnerability in federated share exists in versions prior to 19.0.11, 20.0.10, and 21.0.2.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (1.84%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
Nextcloud Server is a Nextcloud package that handles data storage. A vulnerability in federated share exists in versions prior to 19.0.11, 20.0.10, and 21.0.2. An attacker can gain access to basic information about users of a server by accessing a public link that a legitimate server user added as a federated share. This happens because Nextcloud supports sharing registered users with other Nextcloud servers, which can be done automatically when selecting the "Add server automatically once a federated share was created successfully" setting. The vulnerability is patched in versions 19.0.11, 20.0.10, and 21.0.2 As a workaround, disable "Add server automatically once a federated share was created successfully" in the Nextcloud settings.
- CVSS 3.1
- 8.6 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N
- EPSS
- 1.84% probability · 78th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-284
- Affected
- nextcloud/nextcloud server
- Source
- security-advisories@github.com
References
- https://github.com/nextcloud/security-advisories/security/advisories/GHSA-j875-vr2q-h6x6Third Party Advisory
- https://hackerone.com/reports/1167853Permissions Required, Third Party Advisory
- https://security.gentoo.org/glsa/202208-17Third Party Advisory
- https://github.com/nextcloud/security-advisories/security/advisories/GHSA-j875-vr2q-h6x6Third Party Advisory
- https://hackerone.com/reports/1167853Permissions Required, Third Party Advisory
- https://security.gentoo.org/glsa/202208-17Third Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.