SB2026083168 - Inefficient Algorithmic Complexity in linkify-it

Description

This security bulletin contains information about 1 vulnerability.

1) Inefficient Algorithmic Complexity (CVE-ID: CVE-2026-59887)

CWE-ID: CWE-407 - Inefficient Algorithmic Complexity

CVSSv4: 8.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]

The vulnerability allows a remote attacker to cause a denial of service.

The vulnerability exists due to inefficient algorithmic complexity in the mailto: schema validator scan loop when processing user-supplied text containing repeated mailto: sequences. A remote attacker can send specially crafted input to cause a denial of service.

The issue is reachable through the documented .test() and .match() API and through markdown rendering with linkification enabled.

Remediation

Install update from vendor's website.

References

• https://github.com/advisories/GHSA-v245-v573-v5vm
• https://github.com/markdown-it/linkify-it/commit/105e5d77f7d119871d2b2d86ed208568eb3e7ffe