Medium severity · published Jun 9, 2021
CVE-2021-33829
A cross-site scripting (XSS) vulnerability in the HTML Data Processor in CKEditor 4 4.14.0 through 4.16.x before 4.16.1 allows remote attackers to inject executable JavaScript…
6.1
CVSS
3.2%
EPSS
No
On KEV
Description
A cross-site scripting (XSS) vulnerability in the HTML Data Processor in CKEditor 4 4.14.0 through 4.16.x before 4.16.1 allows remote attackers to inject executable JavaScript code through a crafted comment because --!> is mishandled.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
Required
Confidentiality
Low
Integrity
Low
Availability
None
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)3.2% · higher than 88% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
DR
Drupal · Drupal
8.9.0 before 8.9.16; 9.0.0 before 9.0.14; 9.1.0 before 9.1.9 · source: NVD
CK
Ckeditor · Ckeditor
4.14.0 before 4.16.1 · source: NVD
DL
Debian Linux · Debian
9.0 · source: NVD
FE
Fedora · Fedoraproject
33; 34; 35 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-33829
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-33829
Patch
https://ckeditor.com/blog/ckeditor-4.16.1-with-accessibility-enhancements/#improvements-for-comments-in-html-parser
Mailing List
https://lists.debian.org/debian-lts-announce/2021/11/msg00007.html
lists.fedoraproject.org
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/NYA354LJP47KCVJMTUO77ZCX3ZK42G3T/
lists.fedoraproject.org
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/UVOYN2WKDPLKCNILIGEZM236ABQASLGW/
lists.fedoraproject.org
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/WAGNWHFIQAVCP537KFFS2A2GDG66J7XD/
Patch
https://www.drupal.org/sa-core-2021-003
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