{"id":"CVE-2026-110869","aliases":[],"url":"https://o3.security/vulnerability/CVE-2026-110869","summary":"Nodemailer 3.0.0 before 10.0.13 has a regular expression denial of service in SMTPConnection._actionEHLO, whose four AUTH mechanism detection regexes contain overlapping whitespace…","details":"Nodemailer 3.0.0 before 10.0.13 has a regular expression denial of service in SMTPConnection._actionEHLO, whose four AUTH mechanism detection regexes contain overlapping whitespace sub-patterns that backtrack quadratically. A malicious or man-in-the-middle SMTP server can reply to EHLO with 250-AUTH, a long whitespace run and a non-matching token, blocking the Node.js event loop for tens of seconds to hours before authentication.","published":"2026-10-14T23:17:28.673","modified":"2026-10-14T23:17:28.673","cvss":{"score":7.5,"severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"},"epss":null,"cisaKev":null,"exploitsKnown":null,"affectedPackages":[],"fix":null,"references":[{"type":"WEB","url":"https://github.com/nodemailer/nodemailer/security/advisories/GHSA-4ffr-jq9g-5ffx"},{"type":"WEB","url":"https://www.vulncheck.com/advisories/nodemailer-3.0.0-before-10.0.13-redos-via-smtp-auth-mechanism-detection-regexes"}],"provenance":{"sources":["OSV.dev","NVD","FIRST.org (EPSS)"],"lastVerified":"2026-10-14T23:17:28.673"}}