CVE-2021-21254

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Summary

CVECVE-2021-21254
StatePUBLIC
Assigner[email protected]
Source PriorityCVE Program / NVD first with legacy fallback
Published2021-01-29 22:15:00 UTC
Updated2023-11-07 03:29:00 UTC
DescriptionCKEditor 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.

Risk And Classification

Problem Types: CWE-400

NVD Known Affected Configurations (CPE 2.3)

TypeVendorProductVersionUpdateEditionLanguage
Application Ckeditor Ckeditor5 All All All All
Application Ckeditor Ckeditor 5 All All All All
Application Ckeditor Ckeditor 5 All All All All

References

ReferenceSourceLinkTags
@ckeditor/ckeditor5-markdown-gfm - npm MISC www.npmjs.com Release Notes, Third Party Advisory
Regular expression Denial of Service in Markdown plugin · Advisory · ckeditor/ckeditor5 · GitHub CONFIRM github.com Third Party Advisory
@ckeditor/ckeditor5-markdown-gfm - npm www.npmjs.com
Release v25.0.0 · ckeditor/ckeditor5 · GitHub MISC github.com Release Notes, Third Party Advisory
CVE Program record CVE.ORG www.cve.org canonical
NVD vulnerability detail NVD nvd.nist.gov canonical, analysis

Legacy QID Mappings

  • 982962 Nodejs (npm) Security Update for @ckeditor/ckeditor5-markdown-gfm (GHSA-hgmg-hhc8-g5wr)
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