CVE-2021-21254 is a Regular Expression Denial of Service (ReDoS) vulnerability affecting the CKEditor 5 Markdown plugin (versions <= 24.0.0). This flaw allows an attacker to craft specific input that abuses the link recognition regular expression, leading to a significant performance degradation and potential browser tab freezes for users. Rated with a CVSS score of 6.5 (Medium), the vulnerability has a low attack complexity and can cause high availability impact, though it does not compromise confidentiality or integrity. There is no evidence of active exploitation, public exploit code, or significant community discussion surrounding this CVE.
| Vendor | Product | Version(s) | CPE |
|---|---|---|---|
< 25.0.0CPE matchmatch criteria | cpe:2.3:a:ckeditor:ckeditor5:*:*:*:*:*:*:*:* |
CVSS version used by this source: 3.1
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
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No media coverage found for this CVE.
The average CVE in this peer group has 0.0 InfoSec Media, 0.0 Vendor Blog, and 0.0 Security Researcher mentions.