Vulnerability Name:

CVE-2021-41239 (CCN-221294)

Assigned:2021-09-15
Published:2022-03-08
Updated:2022-10-24
Summary:Nextcloud server is a self hosted system designed to provide cloud style services. In affected versions the User Status API did not consider the user enumeration settings by the administrator. This allowed a user to enumerate other users on the instance, even when user listings where disabled. It is recommended that the Nextcloud Server is upgraded to 20.0.14, 21.0.6 or 22.2.1. There are no known workarounds.
CVSS v3 Severity:5.3 Medium (CVSS v3.1 Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N)
4.6 Medium (Temporal CVSS v3.1 Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N/E:U/RL:O/RC:C)
Exploitability Metrics:Attack Vector (AV): Network
Attack Complexity (AC): Low
Privileges Required (PR): None
User Interaction (UI): None
Scope:Scope (S): Unchanged
Impact Metrics:Confidentiality (C): Low
Integrity (I): None
Availibility (A): None
5.3 Medium (CCN CVSS v3.1 Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N)
4.6 Medium (CCN Temporal CVSS v3.1 Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N/E:U/RL:O/RC:C)
Exploitability Metrics:Attack Vector (AV): Network
Attack Complexity (AC): Low
Privileges Required (PR): None
User Interaction (UI): None
Scope:Scope (S): Unchanged
Impact Metrics:Confidentiality (C): Low
Integrity (I): None
Availibility (A): None
CVSS v2 Severity:5.0 Medium (CVSS v2 Vector: AV:N/AC:L/Au:N/C:P/I:N/A:N)
Exploitability Metrics:Access Vector (AV): Network
Access Complexity (AC): Low
Authentication (Au): None
Impact Metrics:Confidentiality (C): Partial
Integrity (I): None
Availibility (A): None
5.0 Medium (CCN CVSS v2 Vector: AV:N/AC:L/Au:N/C:P/I:N/A:N)
Exploitability Metrics:Access Vector (AV): Network
Access Complexity (AC): Low
Athentication (Au): None
Impact Metrics:Confidentiality (C): Partial
Integrity (I): None
Availibility (A): None
Vulnerability Type:CWE-200
Vulnerability Consequences:Obtain Information
References:Source: MITRE
Type: CNA
CVE-2021-41239

Source: XF
Type: UNKNOWN
nextcloud-cve202141239-info-disc(221294)

Source: CCN
Type: Nextcloud GIT Repository
User enumeration setting not obeyed in User Status API

Source: CONFIRM
Type: Issue Tracking, Third Party Advisory
https://github.com/nextcloud/security-advisories/security/advisories/GHSA-g722-cm3h-8wrx

Source: MISC
Type: Issue Tracking, Patch, Third Party Advisory
https://github.com/nextcloud/server/issues/27122

Source: MISC
Type: Patch, Third Party Advisory
https://github.com/nextcloud/server/pull/29260

Source: GENTOO
Type: Third Party Advisory
GLSA-202208-17

Vulnerable Configuration:Configuration 1:
  • cpe:/a:nextcloud:nextcloud_server:*:*:*:*:*:*:*:* (Version < 20.0.14)
  • OR cpe:/a:nextcloud:nextcloud_server:*:*:*:*:*:*:*:* (Version >= 21.0.0 and < 21.0.6)
  • OR cpe:/a:nextcloud:nextcloud_server:22.2.0:*:*:*:*:*:*:*

    • Configuration CCN 1:
  • cpe:/a:nextcloud:nextcloud_server:20.0.0:-:*:*:*:*:*:*
  • OR cpe:/a:nextcloud:nextcloud_server:21.0.0:-:*:*:*:*:*:*

    • * Denotes that component is vulnerable
    BACK
    nextcloud nextcloud server *
    nextcloud nextcloud server *
    nextcloud nextcloud server 22.2.0
    nextcloud nextcloud server 20.0.0
    nextcloud nextcloud server 21.0.0 -