CVE-2018-25110: marked — Exploit & Fix

Description

Marked prior to version 0.3.17 is vulnerable to a Regular Expression Denial of Service (ReDoS) attack due to catastrophic backtracking in several regular expressions used for parsing HTML tags and markdown links. An attacker can exploit this vulnerability by providing specially crafted markdown input, such as deeply nested or repetitively structured brackets or tag attributes, which cause the parser to hang and lead to a Denial of Service.

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CVSS v3.1 Score

7.5

HIGH

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Weakness Type (CWE)

CWE-1333 CWE-1333

Affected Products

Vendor	Product	Versions
marked_project	marked	< 0.3.17

References

Advisories & Patches

https://github.com/markedjs/marked/commit/20bfc106013ed45713a21672ad4a34df94dcd485 https://github.com/markedjs/marked/pull/1083

Exploits

https://github.com/Checkmarx/Vulnerabilities-Proofs-of-Concept/tree/main/2018/CVE-2018-25110

Other References

https://github.com/markedjs/marked/issues/1070

Frequently Asked Questions

What is CVE-2018-25110? +

Marked prior to version 0.3.17 is vulnerable to a Regular Expression Denial of Service (ReDoS) attack due to catastrophic backtracking in several regular expressions used for parsing HTML tags and markdown links. An attacker can exploit this vulnerability by providing specially crafted markdown input, such as deeply nested or repetitively structured brackets or tag attributes, which cause the parser to hang and lead to a Denial of Service. It has a CVSS v3.1 base score of 7.5 (HIGH).

How severe is CVE-2018-25110? +

CVE-2018-25110 has a CVSS v3.1 score of 7.5 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching.

What products are affected by CVE-2018-25110? +

CVE-2018-25110 affects products from marked_project, specifically: marked. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2018-25110? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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CVE-2018-25110