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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- Required
What an attacker can affect
- Confidentiality
- High
- Integrity
- Low
- Availability
- None
Exploit likelihood
What each source reports
CVE List Score used
7.6
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.
- Record
CVE-2021-32808- CVSS 3.1
- 7.6 High
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:L/A:N - Weakness
- CWE-79
- Updated
- 2026-11-02
EUVDEUVD-2021-1585
7.6
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.
- Record
EUVD-2021-1585- CVSS 3.1
- 7.6 High
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:L/A:N - Updated
- 2026-11-03
GitHub AdvisoriesGHSA-6226-h7ff-ch6c
7.6
Widget feature vulnerability allowing to execute JavaScript code using undo functionality
Affected packages
The vulnerability has been discovered in Widget plugin if used alongside Undo feature.
Impact
A potential vulnerability has been discovered in CKEditor 4 Widget package. The vulnerability allowed 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.
Patches
The problem has been recognized and patched. The fix will be available in version 4.16.2.
For more information
Email us at [email protected] if you have any questions or comments about this advisory.
Acknowledgements
The CKEditor 4 team would like to thank Anton Subbotin (skavans) for recognizing and reporting this vulnerability.
- Record
GHSA-6226-h7ff-ch6c- CVSS 3.1
- 7.6 High
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:L/A:N - Weakness
- CWE-79
- Updated
- 2026-11-02
NVD
7.6
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.
- Record
CVE-2021-32808- CVSS 3.1
- 7.6 High
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:L/A:N - CVSS 3.1
- 5.4 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N - CVSS 2.0
- 3.5 Low
AV:N/AC:M/Au:S/C:N/I:P/A:N - Weakness
- CWE-79
- Updated
- 2026-11-02
OSV
5.4
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.
- Record
CVE-2021-32808- CVSS 3.1
- 5.4 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N - Updated
- 2026-11-02
OSVDEBIAN-CVE-2021-32808
5.4
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.
- Record
DEBIAN-CVE-2021-32808- CVSS 3.1
- 5.4 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N - Updated
- 2026-11-02
OSVGHSA-6226-h7ff-ch6c
7.6
Widget feature vulnerability allowing to execute JavaScript code using undo functionality
Affected packages
The vulnerability has been discovered in Widget plugin if used alongside Undo feature.
Impact
A potential vulnerability has been discovered in CKEditor 4 Widget package. The vulnerability allowed 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.
Patches
The problem has been recognized and patched. The fix will be available in version 4.16.2.
For more information
Email us at [email protected] if you have any questions or comments about this advisory.
Acknowledgements
The CKEditor 4 team would like to thank Anton Subbotin (skavans) for recognizing and reporting this vulnerability.
- Record
GHSA-6226-h7ff-ch6c- CVSS 3.1
- 7.6 High
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:L/A:N - Weakness
- CWE-79
- Updated
- 2026-11-02
OSVUBUNTU-CVE-2021-32808
5.4
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.
- Record
UBUNTU-CVE-2021-32808- CVSS 3.1
- 5.4 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N - CVSS 3.1
- 7.6 High
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:L/A:N - Updated
- 2026-11-02
OSVUSN-5340-1 No score
ckeditor vulnerabilities
Kyaw Min Thein discovered that CKEditor incorrectly handled certain inputs. An attacker could possibly use this issue to execute arbitrary code. This issue only affects Ubuntu 18.04 LTS. (CVE-2018-9861)
Micha Bentkowski discovered that CKEditor incorrectly handled certain inputs. An attacker could possibly use this issue to execute arbitrary code. This issue only affects Ubuntu 18.04 LTS and Ubuntu 20.04 LTS. (CVE-2020-9281)
Anton Subbotin discovered that CKEditor incorrectly handled certain inputs. An attacker could possibly use this issue to execute arbitrary code. This issue only affects Ubuntu 21.10. (CVE-2021-32808)
Anton Subbotin discovered that CKEditor incorrectly handled certain inputs. An attacker could possibly use this issue to inject arbitrary code. (CVE-2021-32809)
Or Sahar discovered that CKEditor incorrectly handled certain inputs. An attacker could possibly use this issue to execute arbitrary code. This issue only affects Ubuntu 18.04 LTS and Ubuntu 20.04 LTS. (CVE-2021-33829)
Mika Kulmala discovered that CKEditor incorrectly handled certain inputs. An attacker could possibly use this issue to execute arbitrary code. (CVE-2021-37695)
- Record
USN-5340-1- Updated
- 2026-11-02
Affected products
- ckeditor
- ckeditor ckeditor4
- fedoraproject fedora
- oracle application express
- oracle banking party management
- oracle commerce guided search
- oracle commerce merchandising
- oracle documaker
- oracle financial services analytical applications infrastructure
- oracle financial services model management and governance
- oracle jd edwards enterpriseone tools
- oracle peoplesoft enterprise peopletools
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Affected packages
| Package | Affected | Fixed |
|---|---|---|
ckeditor4npm |
4.13.0 up to 4.16.2 | 4.16.2 |
ckeditorDebian:12 |
before 4.16.2+dfsg-1 | 4.16.2+dfsg-1 |
ckeditorUbuntu:18.04:LTS From an advisory covering 6 CVEs |
before 4.5.7+dfsg-2ubuntu0.18.04.1, plus listed versions 4.5.7+dfsg-2 |
4.5.7+dfsg-2ubuntu0.18.04.1 |
ckeditorUbuntu:20.04:LTS From an advisory covering 6 CVEs |
before 4.12.1+dfsg-1ubuntu0.1, plus listed versions 4.11.1+dfsg-14.12.1+dfsg-1 |
4.12.1+dfsg-1ubuntu0.1 |
History
| Recorded | Changed | Sources |
|---|---|---|
| affected, facts | ||
| affected | ||
| aliases | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2021-32808 is a high vulnerability (CVSS 7.6) in Ckeditor, published August 12, 2021. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 1.19%, the 68th percentile. Fixed in ckeditor4 4.16.2.
References
github.com/ckeditor/ckeditor4/security/advisories/GHSA-6226-h7ff-ch6c
github.com/ckeditor/ckeditor4/releases/tag/4.16.2
lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/NYA354LJP47KCVJMTUO77ZCX3ZK42G3T
lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/UVOYN2WKDPLKCNILIGEZM236ABQASLGW
lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/WAGNWHFIQAVCP537KFFS2A2GDG66J7XD
oracle.com/security-alerts/cpuoct2021.html
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oracle.com/security-alerts/cpujan2022.html
nvd.nist.gov/vuln/detail/CVE-2021-32808
lists.fedoraproject.org/archives/list/[email protected]/message/NYA354LJP47KCVJMTUO77ZCX3ZK42G3T
lists.fedoraproject.org/archives/list/[email protected]/message/UVOYN2WKDPLKCNILIGEZM236ABQASLGW
lists.fedoraproject.org/archives/list/[email protected]/message/WAGNWHFIQAVCP537KFFS2A2GDG66J7XD
github.com/advisories/GHSA-6226-h7ff-ch6c
security-tracker.debian.org/tracker/CVE-2021-32808
github.com/ckeditor/ckeditor4
ubuntu.com/security/CVE-2021-32808
ubuntu.com/security/notices/USN-5340-1
cve.org/CVERecord?id=CVE-2021-32808
ubuntu.com/security/CVE-2018-9861
ubuntu.com/security/CVE-2020-9281
ubuntu.com/security/CVE-2021-32809
ubuntu.com/security/CVE-2021-33829
ubuntu.com/security/CVE-2021-37695