CVE-2026-100700: Nodemailer

High severity, CVSS 7.5. EPSS: 0.3% chance of exploitation in the next 30 days.

nodemailer before 10.0.6 contains a denial of service vulnerability in the addressparser free-text fallback regex pattern that exhibits quadratic backtracking behavior. Attackers can supply crafted email header values with long whitespace-free runs to block the Node.js event loop for tens of seconds, causing service unavailability.

Affected products

• Nodemailer Nodemailer: before 10.0.6 (fixed in 10.0.6)

Published 2026-09-26. Last modified 2026-09-30.