CVE-2026-92598

Description

Nodemailer before 9.1.0 fails to apply UTS-46 normalization when encoding international domain names, causing the domain resolver to compute a different Punycode A-label than standards-compliant parsers. Attackers can craft recipient addresses with invisible characters or compatibility mappings that pass domain allow-list checks but are delivered to attacker-controlled domains via SMTP.

CVSS Vector

References

• https://github.com/nodemailer/nodemailer/commit/259c32d
• https://github.com/nodemailer/nodemailer/commit/b212ac4
• https://github.com/nodemailer/nodemailer/security/advisories/GHSA-wmmp-3585-3rmp
• https://www.vulncheck.com/advisories/nodemailer-before-9.1.0-idn-punycode-domain-allow-list-bypass
• https://github.com/nodemailer/nodemailer/security/advisories/GHSA-wmmp-3585-3rmp