CVE-2026-92596: Nodemailer before 9.1.0 Denial of Service via addressparser
Nodemailer before 9.1.0 contains a quadratic time complexity vulnerability in the addressparser component that allows remote attackers to cause denial of service by supplying a crafted comma-separated address list. Attackers can send a single email with a large number of addresses to block the Node.js event loop for extended periods, consuming 100% CPU and freezing the process.
Affected Software
Event History
Frequently Asked Questions
Who can exploit this issue?
A remote attacker can exploit it without privileges or user interaction by supplying a crafted comma-separated address list in a single email.
What is the operational impact of a successful attack?
Processing the address list can consume 100% CPU and block the Node.js event loop for an extended period, freezing the affected process.
Which deployments should be prioritized for remediation?
Prioritize Nodemailer deployments that parse attacker-controlled email or address-list input, since the attack depends on an attacker being able to submit a message containing a large number of addresses.