Nodemailer: Recipient-domain validation bypass via RFC 5322 comment mis-parsing leads to email delivery to an attacker-controlled domain

Summary Nodemailer's email-address parser treats an RFC 5322 comment ... inside the domain as a point to concatenate the surrounding text, rather than as folding whitespace CFWS that terminates the domain. Consequently a recipient address such as [email protected] is parsed and delivere...

CVE-2026-42499

CVE-2026-42499 affects the net/mail package’s consumePhrase routine, where pathological inputs can trigger DoS due to quadratic string concatenation when parsing RFC 5322 email addresses. This is documented across multiple feeds (NVD, CVE list, Debian, CIRCL, OSV GO-2026-4977, vulnrichment), indi...

HackerOne: Attacker may be able to bounce enough emails which suspend HackerOne's SES service and cause a DoS of HackerOne's email service

This was a DoS based on triggering a lot of bounced emails via SES service which could put our email sending up for review with AWS. The vulnerability was due to unrestricted invitations on sandbox programs which allowed an attacker to generate an infinite number of bounced emails. We had applied...