CVE-2021-21391

mediumPriorität · verfolgen · 27EPSS 0.017 · 77. PerzentilEUUS
grimoire priorityP3 · Track
Exploitable?
—
no known exploitation
Likely / severe?
1.67% (77th) EPSS
CVSS 4.3 · medium
Is it mine?
17 products
Prüfe deine Angriffsfläche
Who says so?
4 sources
cnnvd · enisa_euvd · nvd · osv

EPSS · bewertet 2026-10-27

CKEditor 5 provides a WYSIWYG editing solution. This CVE affects the following npm packages: ckeditor5-engine, ckeditor5-font, ckeditor5-image, ckeditor5-list, ckeditor5-markdown-gfm, ckeditor5-media-embed, ckeditor5-paste-from-office, and ckeditor5-widget. Following an internal audit, a regular expression denial of service (ReDoS) vulnerability has been discovered in multiple CKEditor 5 packages. The vulnerability allowed to abuse particular regular expressions, which could cause a significant performance drop resulting in a browser tab freeze. It affects all users using the CKEditor 5 packages listed above at version <= 26.0.0. The problem has been recognized and patched. The fix will be available in version 27.0.0.

01

cvss

Technischer Schweregrad, 0–10. Eine Zeile je Quelle.

6.5
010

Basiswert 0–10 · höher = schwerwiegender · Vektor überfahren zum Auflösen

v2.04.3mediumAV:N/AC:M/Au:N/C:N/I:N/A:Pprimary · NVD / NIST USAusnutzbarkeit 8.6 · Auswirkung 2.9
v3.16.5mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:Hprimary · NVD / NIST USAusnutzbarkeit 2.8 · Auswirkung 3.6
v3.16.5mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:Hsecondary · ENISA EU
v3.16.5mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:Hsecondary · security-advisories@github.comAusnutzbarkeit 2.8 · Auswirkung 3.6
v3.16.5mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:Hsecondary · OSV
v3.16mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H/E:Usecondary · CVSS-BT (t0sche)
02

schwächen

Die CWE-Schwächeklassen, zu denen dies gehört.

03

betroffene Produkte (17)

Betroffene Produkte und Versionsbereiche.

04

Advisories (1)

Hersteller- und Ökosystem-Meldungen dazu.

  • GHSA-3rh3-wfr4-76mjRegular expression Denial of Service in multiple packages2021-04-06ghsa · osvUS

    ### Impact A regular expression denial of service (ReDoS) vulnerability has been discovered in multiple CKEditor 5 packages. The vulnerability allowed to abuse particular regular expressions, which could cause a significant performance drop resulting in a browser tab freeze. It affects all users using the CKEditor 5 packages listed above at version <= 26.0.0. ### Patches The problem has been recognized and patched. The fix will be available in version 27.0.0. ### For more information Email us at security@cksource.com if you have any questions or comments about this advisory. ### Acknowledgements The CKEditor 5 team would like to thank Yeting Li for recognizing and reporting these vulnerabilities.

05

auch bekannt als (3)

Weitere Namen und Kennungen dieser Entität.

06

quellen

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veröffentlicht 2021-04-29geändert 2026-06-17
07

Referenzen (28)

Externe Belege — Patches, Meldungen, Analysen.

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