Vulnerabilities in pkg:npm/ckeditor4-dev

PACKAGE
Advisory Identifier: GHSA-jv4c-7jqq-m34x
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Advisory Summary

CVE-2021-26271 is a MODERATE (CVSS 6.5) denial of service vulnerability (CWE-1333: Inefficient Regular Expression Complexity) affecting Ckeditor4 dev libraries in the npm ecosystem. The issue involves ckeditor 4 redos vulnerability. Remediation is available by upgrading affected packages to version 4.16.

1 Known Advisory Record(s)
Package Vulnerability Intelligence

pkg:npm/ckeditor4-dev

1 Known Advisory Record(s)

Vulnerability advisories affecting package pkg:npm/ckeditor4-dev. Select an advisory below to view technical details or fixes.

Advisory ID CVE / NVD Severity Summary
GHSA-jv4c-7jqq-m34x CVE-2021-26271 MODERATE CKEditor 4 ReDoS Vulnerability

CVE-2021-26271 at a Glance

CVE Identifier CVE-2021-26271
GHSA Identifier GHSA-jv4c-7jqq-m34x
Severity MODERATE
CVSS v3.1 Base Score 6.5
CWE Classification CWE-1333: Inefficient Regular Expression Complexity
Affected Product Ckeditor4 dev
Package Ecosystem npm
Published Date
Last Updated

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).

Attack Vector Network (AV:N)
Attack Complexity Low (AC:L)
Privileges Required None (PR:N)
User Interaction Required (UI:R)
Scope Unchanged (S:U)
Confidentiality None (C:N)
Integrity None (I:N)
Availability High (A:H)

How to Fix CVE-2021-26271

To remediate this vulnerability, upgrade all affected Ckeditor4 dev dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

ckeditor4-dev fixed: 4.16 
npm install ckeditor4-dev@4.16
Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release: 

npm ls ckeditor4-dev

How to Check if You Are Affected

To determine whether your Node.js application is affected by CVE-2021-26271, inspect your project dependencies using npm:

npm ls ckeditor4-dev

Analyze the terminal output to locate any version of Ckeditor4 dev in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 4.16), your application is affected.

Note: The npm ls ckeditor4-dev 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-1333: Inefficient Regular Expression Complexity, where the product uses a regular expression with a worst-case computational complexity that is inefficient and possibly exponential. In Ckeditor4 dev, 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

It was possible to execute a ReDoS-type attack inside CKEditor 4 before 4.16 by persuading a victim to paste crafted text into the Styles input of specific dialogs (in the Advanced Tab for Dialogs plugin).

CVE-2021-26271 Affected Ckeditor4 dev Versions

1 component(s)
Fixed Versions:
4.16
Product / Package Ecosystem Affected Versions Fixed Version
ckeditor4-dev
npm/ckeditor4-dev
npm
< 4.16
4.16

References

NVD — CVE-2021-26271 NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-26271
Ckeditor4 dev Source Repository REPOSITORY
https://github.com/ckeditor/ckeditor4
Ckeditor4 dev Source Repository REPOSITORY
https://github.com/ckeditor/ckeditor4/blob/major/CHANGES.md#ckeditor-416
web.archive.org/web/20210128132707/... WEB
https://web.archive.org/web/20210128132707/https://ckeditor.com/blog/CKEditor-4.16-with-improved-image-pasting-High-Contrast-support-and-a-new-color-API/#security-comes-first
Ckeditor4 dev Security Information SECURITY
https://www.oracle.com//security-alerts/cpujul2021.html
Ckeditor4 dev Security Information SECURITY
https://www.oracle.com/security-alerts/cpuoct2021.html

Frequently Asked Questions

What is CVE-2021-26271?
CVE-2021-26271 is a security vulnerability in Ckeditor4 dev involving CKEditor 4 ReDoS Vulnerability under CWE-1333: Inefficient Regular Expression Complexity.
Which Ckeditor4 dev versions are affected?
Affected versions include releases prior to 4.16 across affected packages: ckeditor4-dev.
What version fixes CVE-2021-26271?
Upgrading to 4.16 (or the latest patched release for your respective branch) resolves the vulnerability.
Is ckeditor4-dev affected?
Yes, ckeditor4-dev is affected in releases prior to 4.16. Upgrade your dependency to 4.16 or later.
What is the CVSS score of CVE-2021-26271?
CVE-2021-26271 has a CVSS v3.1 base score of 6.5 (MODERATE) with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H.
What CWE is associated with CVE-2021-26271?
CVE-2021-26271 is classified under CWE-1333: Inefficient Regular Expression Complexity (The product uses a regular expression with a worst-case computational complexity that is inefficient and possibly exponential.).
How can I check npm dependencies for CVE-2021-26271?
Run the dependency tree command: 'npm ls ckeditor4-dev'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.
Machine-readable OSV JSON OSV v1.5 Schema
Normalized schema output
View Raw JSON 
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-jv4c-7jqq-m34x",
  "modified" : "2024-04-22T23:14:44Z",
  "published" : "2022-05-24T17:40:21Z",
  "aliases" : [ "CVE-2021-26271" ],
  "summary" : "CKEditor 4 ReDoS Vulnerability",
  "details" : "It was possible to execute a ReDoS-type attack inside CKEditor 4 before 4.16 by persuading a victim to paste crafted text into the Styles input of specific dialogs (in the Advanced Tab for Dialogs plugin).",
  "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" : "ckeditor4-dev"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "4.16"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2021-26271"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/ckeditor/ckeditor4"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/ckeditor/ckeditor4/blob/major/CHANGES.md#ckeditor-416"
  }, {
    "type" : "WEB",
    "url" : "https://web.archive.org/web/20210128132707/https://ckeditor.com/blog/CKEditor-4.16-with-improved-image-pasting-High-Contrast-support-and-a-new-color-API/#security-comes-first"
  }, {
    "type" : "WEB",
    "url" : "https://www.oracle.com//security-alerts/cpujul2021.html"
  }, {
    "type" : "WEB",
    "url" : "https://www.oracle.com/security-alerts/cpuoct2021.html"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-1333" ],
    "severity" : "MODERATE",
    "github_reviewed" : true,
    "github_reviewed_at" : "2024-04-22T23:14:44Z",
    "nvd_published_at" : "2021-01-26T21:15:00Z"
  }
}