Vulnerability Name:

CVE-2021-32733 (CCN-205338)

Assigned:2021-07-12
Published:2021-07-12
Updated:2021-07-14
Summary:Nextcloud Text is a collaborative document editing application that uses Markdown. A cross-site scripting vulnerability is present in versions prior to 19.0.13, 20.0.11, and 21.0.3. The Nextcloud Text application shipped with Nextcloud server used a `text/html` Content-Type when serving files to users. Due the strict Content-Security-Policy shipped with Nextcloud, this issue is not exploitable on modern browsers supporting Content-Security-Policy. The issue was fixed in versions 19.0.13, 20.0.11, and 21.0.3. As a workaround, use a browser that has support for Content-Security-Policy.
CVSS v3 Severity:6.1 Medium (CVSS v3.1 Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N)
5.8 Medium (Temporal CVSS v3.1 Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N/E:H/RL:O/RC:C)
Exploitability Metrics:Attack Vector (AV): Network
Attack Complexity (AC): Low
Privileges Required (PR): None
User Interaction (UI): Required
Scope:Scope (S): Changed
Impact Metrics:Confidentiality (C): Low
Integrity (I): Low
Availibility (A): None
6.1 Medium (CCN CVSS v3.1 Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N)
5.8 Medium (CCN Temporal CVSS v3.1 Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N/E:H/RL:O/RC:C)
Exploitability Metrics:Attack Vector (AV): Network
Attack Complexity (AC): Low
Privileges Required (PR): None
User Interaction (UI): Required
Scope:Scope (S): Changed
Impact Metrics:Confidentiality (C): Low
Integrity (I): Low
Availibility (A): None
CVSS v2 Severity:4.3 Medium (CVSS v2 Vector: AV:N/AC:M/Au:N/C:N/I:P/A:N)
Exploitability Metrics:Access Vector (AV): Network
Access Complexity (AC): Medium
Authentication (Au): None
Impact Metrics:Confidentiality (C): None
Integrity (I): Partial
Availibility (A): None
5.5 Medium (CCN CVSS v2 Vector: AV:N/AC:L/Au:S/C:P/I:P/A:N)
Exploitability Metrics:Access Vector (AV): Network
Access Complexity (AC): Low
Athentication (Au): Single_Instance
Impact Metrics:Confidentiality (C): Partial
Integrity (I): Partial
Availibility (A): None
Vulnerability Type:CWE-79
Vulnerability Consequences:Cross-Site Scripting
References:Source: MITRE
Type: CNA
CVE-2021-32733

Source: XF
Type: UNKNOWN
nextcloud-cve202132733-xss(205338)

Source: CCN
Type: Nextcloud GIT Repository
XSS in Nextcloud Text application

Source: CONFIRM
Type: Third Party Advisory
https://github.com/nextcloud/security-advisories/security/advisories/GHSA-x4w3-jhcr-57pq

Source: MISC
Type: Patch, Third Party Advisory
https://github.com/nextcloud/text/pull/1689

Source: MISC
Type: Permissions Required
https://hackerone.com/reports/1241460

Vulnerable Configuration:Configuration 1:
  • cpe:/a:nextcloud:nextcloud_server:*:*:*:*:*:*:*:* (Version < 19.0.13)
  • OR cpe:/a:nextcloud:nextcloud_server:*:*:*:*:*:*:*:* (Version >= 20.0.0 and < 20.0.11)
  • OR cpe:/a:nextcloud:nextcloud_server:*:*:*:*:*:*:*:* (Version >= 21.0.0 and < 21.0.3)

    • Configuration CCN 1:
  • cpe:/a:nextcloud:nextcloud_server:20.0.0:-:*:*:*:*:*:*
  • OR cpe:/a:nextcloud:nextcloud_server:19.0.0:-:*:*:*:*:*:*
  • OR cpe:/a:nextcloud:nextcloud_server:21.0.0:-:*:*:*:*:*:*

    • * Denotes that component is vulnerable
    BACK
    nextcloud nextcloud server *
    nextcloud nextcloud server *
    nextcloud nextcloud server *
    nextcloud nextcloud server 20.0.0
    nextcloud nextcloud server 19.0.0 -
    nextcloud nextcloud server 21.0.0 -