Inefficient Regular Expression Complexity in marked (CVE-2022-21681) | HOL Guard CVE

High · CVSS 7.5CVE-2022-21681GHSA-5V2H-R2CX-5XGJ

Inefficient Regular Expression Complexity in marked

Answer in brief

CVE-2022-21681 records a High severity (CVSS 7.5) vulnerability in Inefficient Regular Expression Complexity in marked. The current sources do not mark it as known exploited. The current feed maps marked (npm). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Jan 14, 2022Updated Sep 10, 2026Source checked Sep 10, 2026First seen by HOL Sep 10, 2026Material review Sep 10, 2026

Upstream Advisory

Key facts

Risk: High · CVSS 7.5
Exploitation: Not marked as known exploited
Affected software: 1 mapped package or product
Fix availability: Available

Why this deserves its current priority

CVSS is 7.5. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps marked (npm). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
markednpm	>=0 <4.0.10	4.0.10

Recommended response

Check inventory. Check lockfiles and deployed manifests for marked.
Review the reported fix. Update marked to 4.0.10 if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

Published upstream
Jan 14, 2022
Evidence: source:osv:source_dates:source-dates:record
Source modified
Sep 10, 2026
Evidence: source:osv:source_dates:source-dates:record
First seen by HOL
Sep 10, 2026

Sources and claim methodology

Upstream source description

### Impact _What kind of vulnerability is it?_ Denial of service. The regular expression `inline.reflinkSearch` may cause catastrophic backtracking against some strings. PoC is the following. ```javascript import * as marked from 'marked'; console.log(marked.parse(`[x]: x \\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](`)); ``` _Who is impacted?_ Anyone who runs untrusted markdown through marked and does not use a worker with a time limit. ### Patches _Has the problem been patched?_ Yes _What versions should users upgrade to?_ 4.0.10 ### Workarounds _Is there a way for users to fix or remediate the vulnerability without upgrading?_ Do not run untrusted markdown through marked or run marked on a [worker](https://marked.js.org/using_advanced#workers) thread and set a reasonable time limit to prevent draining resources. ### References _Are there any links users can visit to find out more?_ - https://marked.js.org/using_advanced#workers - https://owasp.org/www-community/attacks/Regular_expression_Denial_of_Service_-_ReDoS ### For more information If you have any questions or comments about this advisory: * Open an issue in [marked](https://github.com/markedjs/marked)

Quoted source text, attributed separately from HOL analysis.