{"id":"CVE-2026-92597","title":"Nodemailer versions >= 6.9.16 and < 9.1.0 mis-parse RFC 5322 comments in email addresses: in lib/addressparser, a comment closed immediately before a non-break character causes the tokenizer to concatenate the atoms surrounding the comme…","summary":"Nodemailer versions >= 6.9.16 and < 9.1.0 mis-parse RFC 5322 comments in email addresses: in lib/addressparser, a comment closed immediately before a non-break character causes the tokenizer to concatenate the atoms surrounding the comme…","severity":"medium","cvss":6.5,"cvssVector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:N","cwe":["CWE-436","CWE-1286"],"vendor":"nodemailer","product":"nodemailer","affected":["nodemailer >= 6.9.16 < 9.1.0"],"published":"2026-09-16","updated":"2026-09-22","sourceUpdated":"2026-09-22T20:25:55.870","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-92597","references":[{"url":"https://github.com/nodemailer/nodemailer/commit/902b63e","label":"disclosure@vulncheck.com"},{"url":"https://github.com/nodemailer/nodemailer/security/advisories/GHSA-cc9r-2j5m-2m83","label":"disclosure@vulncheck.com"},{"url":"https://www.vulncheck.com/advisories/nodemailer-before-9.1.0-email-domain-validation-bypass-via-rfc-5322-comment","label":"disclosure@vulncheck.com"},{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-92597.json"},{"url":"https://access.redhat.com/security/cve/CVE-2026-92597"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2537871"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-92597"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-92597"}],"tags":["nvd","cve.org","csaf","vex","red-hat"],"epss":0.00382,"epssPercentile":0.32063,"ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"partial","timestamp":"2026-09-17T19:17:07.433374Z"},"ingestedAt":"2026-09-16T22:06:50.928Z","slug":"CVE-2026-92597","body":"## Overview\n\nNodemailer versions >= 6.9.16 and < 9.1.0 mis-parse RFC 5322 comments in email addresses: in lib/addressparser, a comment closed immediately before a non-break character causes the tokenizer to concatenate the atoms surrounding the comment instead of treating the comment as folding whitespace that terminates the domain. A recipient address such as user@good-corp.com(x)evil.com is therefore read by Nodemailer as the single domain good-corp.comevil.com (registrable domain comevil.com, which an attacker can register) and used for both the SMTP envelope (RCPT TO) and the emitted To:/From: headers, while a conformant RFC 5322 parser terminates the domain at the comment and reads good-corp.com. An application that validates the recipient domain with a strict RFC 5322 parser (without inspecting parse defects) or a naive prefix/substring allow-list and then hands the raw address to Nodemailer can be induced to deliver mail to a domain the attacker controls. Fixed in 9.1.0.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.\n\n## Vendor advisories\n\n- **Red Hat VEX** · Moderate · affected: Self-service automation portal 2 · no fix planned: Self-service automation portal 2 · updated 2026-09-23 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-92597.json)","depth":"sunlit","depthScore":36,"depthScoreParts":{"impact":35.8,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}