{"cve":"CVE-2026-92597","nvd":{"published":"2026-09-16T22:18:30.700","modified":"2026-09-22T20:25:55.870","status":"Awaiting Analysis","description":"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 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.","cvss_v4":{"vector":"CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N","score":8.3},"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:N","score":6.5},"cwes":["CWE-436"],"references":["https://github.com/nodemailer/nodemailer/commit/902b63e","https://github.com/nodemailer/nodemailer/security/advisories/GHSA-cc9r-2j5m-2m83","https://www.vulncheck.com/advisories/nodemailer-before-9.1.0-email-domain-validation-bypass-via-rfc-5322-comment"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:54:41.405518556+00:00"},"epss":{"cve":"CVE-2026-92597","score":0.00382,"percentile":0.32261,"date":"2026-10-31"},"kev":null,"osv":[{"id":"GHSA-cc9r-2j5m-2m83","url":"https://osv.dev/vulnerability/GHSA-cc9r-2j5m-2m83","summary":"Nodemailer: Recipient-domain validation bypass via RFC 5322 comment mis-parsing leads to email delivery to an attacker-controlled domain","modified":"2026-09-17T11:56:01.670395333Z","packages":[{"ecosystem":"npm","name":"nodemailer","purl":"pkg:npm/nodemailer","ranges":[">=6.9.16 <9.1.0"],"fixed":["9.1.0"]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}