CVE-2021-32688
Nextcloud Server is a Nextcloud package that handles data storage.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (2.31%). 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. 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.
- CVSS 3.1
- 8.8 HIGHCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- EPSS
- 2.31% probability · 82th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-285, CWE-552
- Affected
- nextcloud/nextcloud server · fedoraproject/fedora
- Source
- security-advisories@github.com
References
- https://github.com/nextcloud/security-advisories/security/advisories/GHSA-48m7-7r2r-838rThird Party Advisory
- https://github.com/nextcloud/server/pull/27000Patch, Third Party Advisory
- https://hackerone.com/reports/1193321Permissions Required
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/BVZS26RDME2DYTKET5AECRIZDFUGR2AZ/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/J63NBVPR2AQCAWRNDOZSGRY5II4WS2CZ/
- https://security.gentoo.org/glsa/202208-17Third Party Advisory
- https://github.com/nextcloud/security-advisories/security/advisories/GHSA-48m7-7r2r-838rThird Party Advisory
- https://github.com/nextcloud/server/pull/27000Patch, Third Party Advisory
- https://hackerone.com/reports/1193321Permissions Required
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/BVZS26RDME2DYTKET5AECRIZDFUGR2AZ/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/J63NBVPR2AQCAWRNDOZSGRY5II4WS2CZ/
- https://security.gentoo.org/glsa/202208-17Third Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.