CVE-2021-32808 | Cross-site scripting in ckeditor via abuse of undo functionality

ckeditor is an open source WYSIWYG HTML editor with rich content support. A vulnerability has been discovered in the clipboard Widget plugin if used alongside the undo feature. The vulnerability allows a user to abuse undo functionality using malformed widget HTML, which could result in executing JavaScript code. It affects all users using the CKEditor 4 plugins listed above at version >= 4.13.0. The problem has been recognized and patched. The fix will be available in version 4.16.2.

Published: 2021-08-12 Last update: 2024-11-21 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2021-32808 is rated Moderate Risk (59.3/100): CVSS High severity, with medium exploitation likelihood (EPSS 1.37%). Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2021-32808

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-03-04 0.49% 1.37% +0.88%
2 2026-03-01 1.37% 0.49% -0.88%
3 2026-02-04 — 1.37% —

Full EPSS history (39 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2021-32808

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.6 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:L/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:N)
Service keeps running; no real outage angle.
 2.3 4.7 [email protected]
5.4 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:N)
Service keeps running; no real outage angle.
 2.3 2.7 [email protected]
3.5 2.0 LOW
AV:N/AC:M/Au:S/C:N/I:P/A:N Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:M)
Exploitation needs some favorable conditions, but not exceptional ones.
Authentication (AU:S)
A single authentication is required.
Confidentiality impact (C:N)
No confidentiality impact.
Integrity impact (I:P)
Partial integrity impact.
Availability impact (A:N)
No availability impact.
 6.8 2.9 [email protected]

Weakness enumeration for CVE-2021-32808

GitHub Security Advisory for CVE-2021-32808

GHSA-6226-h7ff-ch6c · Severity: high · Ecosystem: npm — Widget feature vulnerability allowing to execute JavaScript code using undo functionality

OS Trackers for CVE-2021-32808

vendor priority summary link
debian not yet assigned CVE-2021-32808 not yet assigned priority: Debian including 1 source packages (ckeditor), 2 status rows across 2 suites (bookworm, bullseye): open 1, resolved 1. https://security-tracker.debian.org/tracker/CVE-2021-32808
ubuntu medium CVE-2021-32808 medium priority: Ubuntu including 1 source packages (ckeditor), 8 status rows across 8 suites (bionic, focal, hirsute, impish, jammy, trusty, upstream, xenial): not-affected 5, DNE 1, ignored 1, released 1. https://ubuntu.com/security/CVE-2021-32808

Affected software / configurations for CVE-2021-32808

Vendor Product Version Raw CPE
ckeditor ckeditor >= 4.13.0, < 4.16.2 cpe:2.3:a:ckeditor:ckeditor:*:*:*:*:*:node.js:*:*
fedoraproject fedora 33 cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:*
fedoraproject fedora 34 cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:*
fedoraproject fedora 35 cpe:2.3:o:fedoraproject:fedora:35:*:*:*:*:*:*:*
oracle application_express < 21.1.4 cpe:2.3:a:oracle:application_express:*:*:*:*:*:*:*:*
oracle banking_party_management 2.7.0 cpe:2.3:a:oracle:banking_party_management:2.7.0:*:*:*:*:*:*:*
oracle commerce_guided_search 11.3.2 cpe:2.3:a:oracle:commerce_guided_search:11.3.2:*:*:*:*:*:*:*
oracle commerce_merchandising 11.3.2 cpe:2.3:a:oracle:commerce_merchandising:11.3.2:*:*:*:*:*:*:*
oracle documaker 12.6.3 cpe:2.3:a:oracle:documaker:12.6.3:*:*:*:*:*:*:*
oracle documaker 12.6.4 cpe:2.3:a:oracle:documaker:12.6.4:*:*:*:*:*:*:*
oracle financial_services_analytical_applications_infrastructure >= 8.0.7, <= 8.1.1 cpe:2.3:a:oracle:financial_services_analytical_applications_infrastructure:*:*:*:*:*:*:*:*
oracle financial_services_model_management_and_governance 8.0.8.0.0 cpe:2.3:a:oracle:financial_services_model_management_and_governance:8.0.8.0.0:*:*:*:*:*:*:*
oracle financial_services_model_management_and_governance 8.1.0.0.0 cpe:2.3:a:oracle:financial_services_model_management_and_governance:8.1.0.0.0:*:*:*:*:*:*:*
oracle jd_edwards_enterpriseone_tools <= 9.2.6.0 cpe:2.3:a:oracle:jd_edwards_enterpriseone_tools:*:*:*:*:*:*:*:*
oracle peoplesoft_enterprise_peopletools 8.57 cpe:2.3:a:oracle:peoplesoft_enterprise_peopletools:8.57:*:*:*:*:*:*:*
oracle peoplesoft_enterprise_peopletools 8.58 cpe:2.3:a:oracle:peoplesoft_enterprise_peopletools:8.58:*:*:*:*:*:*:*
oracle peoplesoft_enterprise_peopletools 8.59 cpe:2.3:a:oracle:peoplesoft_enterprise_peopletools:8.59:*:*:*:*:*:*:*
oracle siebel_ui_framework <= 21.9 cpe:2.3:a:oracle:siebel_ui_framework:*:*:*:*:*:*:*:*
oracle webcenter_sites 12.2.1.3.0 cpe:2.3:a:oracle:webcenter_sites:12.2.1.3.0:*:*:*:*:*:*:*
oracle webcenter_sites 12.2.1.4.0 cpe:2.3:a:oracle:webcenter_sites:12.2.1.4.0:*:*:*:*:*:*:*

References for CVE-2021-32808

cvelogic Threat Intelligence