Headline
CVE-2022-21680: Build software better, together
Marked is a markdown parser and compiler. Prior to version 4.0.10, the regular expression block.def may cause catastrophic backtracking against some strings and lead to a regular expression denial of service (ReDoS). Anyone who runs untrusted markdown through a vulnerable version of marked and does not use a worker with a time limit may be affected. This issue is patched in version 4.0.10. As a workaround, avoid running untrusted markdown through marked or run marked on a worker thread and set a reasonable time limit to prevent draining resources.
Affected versions
< 4.0.9
Impact
What kind of vulnerability is it?
Denial of service.
The regular expression block.def may cause catastrophic backtracking against some strings.
PoC is the following.
import * as marked from "marked";
marked.parse(`[x]:${’ ‘.repeat(1500)}x ${’ '.repeat(1500)} 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 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
CWEs
CVSS Score
7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H