CVE-2021-21254
CKEditor 5 Markdown plugin Regex Denial of Service (ReDoS)
Description
CKEditor 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.
INFO
Published Date :
Jan. 29, 2021, 10:15 p.m.
Last Modified :
Nov. 7, 2023, 3:29 a.m.
Source :
[email protected]
Remotely Exploitable :
Yes !
Impact Score :
3.6
Exploitability Score :
2.8
Public PoC/Exploit Available at Github
CVE-2021-21254 has a 1 public PoC/Exploit available at Github.
Go to the Public Exploits tab to see the list.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2021-21254.
| URL | Resource |
|---|---|
| https://github.com/ckeditor/ckeditor5/releases/tag/v25.0.0 | Release Notes Third Party Advisory |
| https://github.com/ckeditor/ckeditor5/security/advisories/GHSA-hgmg-hhc8-g5wr | Third Party Advisory |
| https://www.npmjs.com/package/%40ckeditor/ckeditor5-markdown-gfm |
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
List of RegEx DoS (ReDoS) CVEs and resources
security awesome redos regex dos regex-dos pentesting awesome-list regex-security
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2021-21254 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2021-21254 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
CVE Modified by [email protected]
May. 14, 2024
Action Type Old Value New Value -
CVE Modified by [email protected]
Nov. 07, 2023
Action Type Old Value New Value Added Reference GitHub, Inc. https://www.npmjs.com/package/%40ckeditor/ckeditor5-markdown-gfm [No types assigned] Removed Reference GitHub, Inc. https://www.npmjs.com/package/@ckeditor/ckeditor5-markdown-gfm -
CPE Deprecation Remap by [email protected]
Aug. 09, 2022
Action Type Old Value New Value Changed CPE Configuration OR *cpe:2.3:a:ckeditor:ckeditor_5:*:*:*:*:*:*:*:* versions from (excluding) 25.0.0 OR *cpe:2.3:a:ckeditor:ckeditor5:*:*:*:*:*:*:*:* versions from (excluding) 25.0.0 -
Initial Analysis by [email protected]
Feb. 01, 2021
Action Type Old Value New Value Added CVSS V2 NIST (AV:N/AC:L/Au:S/C:N/I:N/A:P) Added CVSS V3.1 NIST AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H Changed Reference Type https://github.com/ckeditor/ckeditor5/releases/tag/v25.0.0 No Types Assigned https://github.com/ckeditor/ckeditor5/releases/tag/v25.0.0 Release Notes, Third Party Advisory Changed Reference Type https://github.com/ckeditor/ckeditor5/security/advisories/GHSA-hgmg-hhc8-g5wr No Types Assigned https://github.com/ckeditor/ckeditor5/security/advisories/GHSA-hgmg-hhc8-g5wr Third Party Advisory Changed Reference Type https://www.npmjs.com/package/@ckeditor/ckeditor5-markdown-gfm No Types Assigned https://www.npmjs.com/package/@ckeditor/ckeditor5-markdown-gfm Release Notes, Third Party Advisory Added CPE Configuration OR *cpe:2.3:a:ckeditor:ckeditor_5:*:*:*:*:*:*:*:* versions up to (excluding) 25.0.0
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2021-21254 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2021-21254
weaknesses.
Exploit Prediction
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days.
0.10 }} 0.00%
score
0.38875
percentile