Vulnerabilities in pkg:npm/@ckeditor/ckeditor5-list
PACKAGECVE-2021-21391 is a MODERATE (CVSS 6.5) denial of service vulnerability (CWE-400: Uncontrolled Resource Consumption) affecting @ckeditor/ckeditor5 engine libraries in the npm ecosystem. The issue involves regular expression denial of service in multiple packages. Remediation is available by upgrading affected packages to version 27.0.0.
pkg:npm/@ckeditor/ckeditor5-list
Vulnerability advisories affecting package pkg:npm/@ckeditor/ckeditor5-list. Select an advisory below to view technical details or fixes.
| Advisory ID | CVE / NVD | Severity | Summary |
|---|---|---|---|
| GHSA-3rh3-wfr4-76mj | CVE-2021-21391 | MODERATE | Regular expression Denial of Service in multiple packages |
CVE-2021-21391 at a Glance
Security Impact
CVSS: 6.5
The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H).
How to Fix CVE-2021-21391
To remediate this vulnerability, upgrade all affected @ckeditor/ckeditor5 engine dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.
npm install @ckeditor/ckeditor5-engine@27.0.0
npm install @ckeditor/ckeditor5-font@27.0.0
npm install @ckeditor/ckeditor5-image@27.0.0
npm install @ckeditor/ckeditor5-list@27.0.0
npm install @ckeditor/ckeditor5-markdown-gfm@27.0.0
npm install @ckeditor/ckeditor5-media-embed@27.0.0
npm install @ckeditor/ckeditor5-paste-from-office@27.0.0
npm install @ckeditor/ckeditor5-widget@27.0.0
Run the following command in your project directory to verify that all resolved dependencies use the patched release:
npm ls @ckeditor/ckeditor5-engine
How to Check if You Are Affected
To determine whether your Node.js application is affected by CVE-2021-21391, inspect your project dependencies using npm:
npm ls @ckeditor/ckeditor5-engine
Analyze the terminal output to locate any version of @ckeditor/ckeditor5 engine in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 27.0.0), your application is affected.
Note: The npm ls @ckeditor/ckeditor5-engine command inspects dependencies declared in your package.json and lockfile; it does not perform automated runtime dynamic scanning.
Technical Details
Vulnerability Mechanism & Technical Analysis
This vulnerability is classified under CWE-400: Uncontrolled Resource Consumption, where the product does not properly control the allocation and maintenance of a limited resource. In @ckeditor/ckeditor5 engine, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.
Source Advisory Statement
CVE-2021-21391 Affected @ckeditor/ckeditor5 engine Versions
8 component(s)| Product / Package | Ecosystem | Affected Versions | Fixed Version |
|---|---|---|---|
|
@ckeditor/ckeditor5-engine
|
npm |
< 27.0.0
|
27.0.0
|
|
@ckeditor/ckeditor5-font
|
npm |
< 27.0.0
|
27.0.0
|
|
@ckeditor/ckeditor5-image
|
npm |
< 27.0.0
|
27.0.0
|
|
@ckeditor/ckeditor5-list
|
npm |
< 27.0.0
|
27.0.0
|
|
@ckeditor/ckeditor5-markdown-gfm
|
npm |
< 27.0.0
|
27.0.0
|
|
@ckeditor/ckeditor5-media-embed
|
npm |
< 27.0.0
|
27.0.0
|
|
@ckeditor/ckeditor5-paste-from-office
|
npm |
< 27.0.0
|
27.0.0
|
|
@ckeditor/ckeditor5-widget
|
npm |
< 27.0.0
|
27.0.0
|
References
Frequently Asked Questions
What is CVE-2021-21391?
Which @ckeditor/ckeditor5 engine versions are affected?
What version fixes CVE-2021-21391?
Is @ckeditor/ckeditor5-engine affected?
Is @ckeditor/ckeditor5-font affected?
What is the CVSS score of CVE-2021-21391?
What CWE is associated with CVE-2021-21391?
How can I check npm dependencies for CVE-2021-21391?
Machine-readable OSV JSON
OSV v1.5 Schema
{
"schema_version" : "1.4.0",
"id" : "GHSA-3rh3-wfr4-76mj",
"modified" : "2021-04-30T17:30:42Z",
"published" : "2021-04-06T17:28:41Z",
"aliases" : [ "CVE-2021-21391" ],
"summary" : "Regular expression Denial of Service in multiple packages",
"details" : "\n### Impact\nA 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.\n\n### Patches\nThe problem has been recognized and patched. The fix will be available in version 27.0.0.\n\n### For more information\nEmail us at security@cksource.com if you have any questions or comments about this advisory.\n\n### Acknowledgements\nThe CKEditor 5 team would like to thank Yeting Li for recognizing and reporting these vulnerabilities.",
"severity" : [ {
"type" : "CVSS_V3",
"score" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H"
} ],
"affected" : [ {
"package" : {
"ecosystem" : "npm",
"name" : "@ckeditor/ckeditor5-engine"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "0"
}, {
"fixed" : "27.0.0"
} ]
} ],
"database_specific" : {
"last_known_affected_version_range" : "<= 26.0.0"
}
}, {
"package" : {
"ecosystem" : "npm",
"name" : "@ckeditor/ckeditor5-font"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "0"
}, {
"fixed" : "27.0.0"
} ]
} ],
"database_specific" : {
"last_known_affected_version_range" : "<= 26.0.0"
}
}, {
"package" : {
"ecosystem" : "npm",
"name" : "@ckeditor/ckeditor5-image"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "0"
}, {
"fixed" : "27.0.0"
} ]
} ],
"database_specific" : {
"last_known_affected_version_range" : "<= 26.0.0"
}
}, {
"package" : {
"ecosystem" : "npm",
"name" : "@ckeditor/ckeditor5-list"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "0"
}, {
"fixed" : "27.0.0"
} ]
} ],
"database_specific" : {
"last_known_affected_version_range" : "<= 26.0.0"
}
}, {
"package" : {
"ecosystem" : "npm",
"name" : "@ckeditor/ckeditor5-markdown-gfm"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "0"
}, {
"fixed" : "27.0.0"
} ]
} ],
"database_specific" : {
"last_known_affected_version_range" : "<= 26.0.0"
}
}, {
"package" : {
"ecosystem" : "npm",
"name" : "@ckeditor/ckeditor5-media-embed"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "0"
}, {
"fixed" : "27.0.0"
} ]
} ],
"database_specific" : {
"last_known_affected_version_range" : "<= 26.0.0"
}
}, {
"package" : {
"ecosystem" : "npm",
"name" : "@ckeditor/ckeditor5-paste-from-office"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "0"
}, {
"fixed" : "27.0.0"
} ]
} ],
"database_specific" : {
"last_known_affected_version_range" : "<= 26.0.0"
}
}, {
"package" : {
"ecosystem" : "npm",
"name" : "@ckeditor/ckeditor5-widget"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "0"
}, {
"fixed" : "27.0.0"
} ]
} ],
"database_specific" : {
"last_known_affected_version_range" : "<= 26.0.0"
}
} ],
"references" : [ {
"type" : "WEB",
"url" : "https://github.com/ckeditor/ckeditor5/security/advisories/GHSA-3rh3-wfr4-76mj"
}, {
"type" : "ADVISORY",
"url" : "https://nvd.nist.gov/vuln/detail/CVE-2021-21391"
}, {
"type" : "WEB",
"url" : "https://github.com/ckeditor/ckeditor5/releases/tag/v27.0.0"
}, {
"type" : "WEB",
"url" : "https://www.npmjs.com/package/@ckeditor/ckeditor5-engine"
}, {
"type" : "WEB",
"url" : "https://www.npmjs.com/package/@ckeditor/ckeditor5-font"
}, {
"type" : "WEB",
"url" : "https://www.npmjs.com/package/@ckeditor/ckeditor5-image"
}, {
"type" : "WEB",
"url" : "https://www.npmjs.com/package/@ckeditor/ckeditor5-list"
}, {
"type" : "WEB",
"url" : "https://www.npmjs.com/package/@ckeditor/ckeditor5-markdown-gfm"
}, {
"type" : "WEB",
"url" : "https://www.npmjs.com/package/@ckeditor/ckeditor5-media-embed"
}, {
"type" : "WEB",
"url" : "https://www.npmjs.com/package/@ckeditor/ckeditor5-paste-from-office"
}, {
"type" : "WEB",
"url" : "https://www.npmjs.com/package/@ckeditor/ckeditor5-widget"
} ],
"database_specific" : {
"cwe_ids" : [ "CWE-400" ],
"severity" : "MODERATE",
"github_reviewed" : true,
"github_reviewed_at" : "2021-03-31T18:37:46Z",
"nvd_published_at" : "2021-04-29T01:15:00Z"
}
}