markdown-it linkify-it up to 5.0.1 Mailto Schema Validator lib/re.mjs test/match resource consumption

Summaryinfo

A vulnerability classified as problematic was found in markdown-it linkify-it up to 5.0.1. Affected is the function test/match of the file lib/re.mjs of the component Mailto Schema Validator. Executing a manipulation can lead to resource consumption. This vulnerability is handled as CVE-2026-59887. The attack can be executed remotely. There is not any exploit available.

Detailsinfo

A vulnerability was found in markdown-it linkify-it up to 5.0.1. It has been declared as problematic. This vulnerability affects the function test/match of the file lib/re.mjs of the component Mailto Schema Validator. The manipulation with an unknown input leads to a resource consumption vulnerability. The CWE definition for the vulnerability is CWE-400. The product does not properly control the allocation and maintenance of a limited resource, thereby enabling an actor to influence the amount of resources consumed, eventually leading to the exhaustion of available resources. As an impact it is known to affect availability. CVE summarizes:

linkify-it is a links recognition library with full Unicode support. Prior to 5.0.2, the mailto: schema validator used by .test() and .match() can be invoked at every mailto: occurrence and scan the remaining input through src_email_name in lib/re.mjs, causing O(n^2) CPU consumption on crafted user text. This issue is fixed in version 5.0.2.

The advisory is shared for download at github.com. This vulnerability was named CVE-2026-59887 since 07/07/2026. The exploitation appears to be easy. The attack can be initiated remotely. No form of authentication is required for a successful exploitation. Successful exploitation requires user interaction by the victim. There are known technical details, but no exploit is available. The MITRE ATT&CK project declares the attack technique as T1499.

Upgrading to version 5.0.2 eliminates this vulnerability.

VulDB is the best source for vulnerability data and more expert information about this specific topic.

Productinfo

Vendor

• markdown-it

Name

• linkify-it

Version

• 5.0.0
• 5.0.1

Website

• Product: https://github.com/markdown-it/linkify-it/

CPE 2.3info

• 🔒
• 🔒

CPE 2.2info

• 🔒
• 🔒

CVSSv4info

CVSSv3info

CVSSv2info

Exploitinginfo

Threat Intelligenceinfo

Countermeasuresinfo

Timelineinfo

Sourcesinfo

Entryinfo

VulDB is the best source for vulnerability data and more expert information about this specific topic.

Discussion