CVE-2026-90776

Description

Nodemailer versions 9.1.0 through 10.0.4 contain a quadratic time complexity vulnerability in the addressparser component when parsing email addresses with RFC 5322 comments. Attackers can craft malicious email headers with comment-separated atoms to consume excessive CPU and block the Node.js event loop for several seconds, causing denial of service.

References

• https://github.com/nodemailer/nodemailer
• https://github.com/nodemailer/nodemailer/blob/v10.0.4/src/addressparser/index.ts#L251
• https://github.com/nodemailer/nodemailer/commit/c07f17518d25aca8ab2ad66968dcbca538c24b89
• https://github.com/nodemailer/nodemailer/releases/tag/v10.0.5
• https://github.com/nodemailer/nodemailer/security/advisories/GHSA-prgh-xp8r-p3m5