CVE-2021-21254: CKEditor 5 is an open source rich text editor framework with a modular architecture. The CKEditor 5 Markdown plugin (@ckeditor/ckeditor5-markdown-gfm) before…

PriorityP434medium6.5CVSS 3.1

AVNACLPRLUINSUCNINAH

EPSS

1.79%

75.6th percentile

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.

Affected

2 ranges

Vendor	Product	Version range	Fixed in
ckeditor	ckeditor5	< 25.0.0	25.0.0
ckeditor	ckeditor5-markdown-gfm	>= 0 < 25.0.0	25.0.0

CVSS provenance

nvdv3.16.5MEDIUMCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

nvdv2.04.0MEDIUMAV:N/AC:L/Au:S/C:N/I:N/A:P

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