CVE-2026-59887CWE-407

CVE-2026-59887

High · published July 8, 2026

CVSS v3.1

7.5

EPSS

Percentile

50.2

In the wild

Unconfirmed

What it is

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 record

Technical detail

CVSS v3.1: 7.5 · HIGH
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CVSS v4.0: Not supplied
EPSS: 0.00644 · 50.2th percentile
Weakness: CWE-407 · Inefficient Algorithmic Complexity
Published: 2026-07-08T21:17Z

Affected products (1)

Product	Versions	Fixed in
markdown-it/linkify-it	< 5.0.2	5.0.2

References (4)

https://github.com/markdown-it/linkify-it/commit/105e5d77f7d119871d2b2d86ed208568eb3e7ffe · [email protected]https://github.com/markdown-it/linkify-it/releases/tag/5.0.2 · [email protected]https://github.com/markdown-it/linkify-it/security/advisories/GHSA-v245-v573-v5vm · [email protected]https://github.com/markdown-it/linkify-it/security/advisories/GHSA-v245-v573-v5vm · 134c704f-9b21-4f2e-91b3-4a467353bcc0

EPSS history

Timeline

08 JUL 15:58Z
linkify-it: Quadratic-complexity DoS via the `mailto:` validator scan-loop on attacker text
cvelistv5