Medium severity · published Jan 29, 2021
CVE-2021-21254
CKEditor 5 is an open source rich text editor framework with a modular architecture
6.5
CVSS
1.8%
EPSS
No
On KEV
Description
CKEditor 5 is an open source rich text editor framework with a modular architecture. The CKEditor 5 Markdown plugin (@ckeditor/ckeditor5-markdown-gfm) before version 25.0.0 has a regex denial of service (ReDoS) vulnerability. The vulnerability allowed to abuse link recognition regular expression, which could cause a significant performance drop resulting in browser tab freeze. It affects all users using CKEditor 5 Markdown plugin at version <= 24.0.0. The problem has been recognized and patched. The fix will be available in version 25.0.0.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)1.8% · higher than 79% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
CK
Ckeditor5 · Ckeditor
before 25.0.0 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-21254
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-21254
Release Notes
https://github.com/ckeditor/ckeditor5/releases/tag/v25.0.0
Third Party Advisory
https://github.com/ckeditor/ckeditor5/security/advisories/GHSA-hgmg-hhc8-g5wr
www.npmjs.com
https://www.npmjs.com/package/%40ckeditor/ckeditor5-markdown-gfm
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