Vulnerability in Nodemailer
CVE-2026-92598
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.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:N.
EPSS exploit prediction
EPSS: 0.004 (33.8th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 34th percentile — 33.8% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.004 · newest: 0.004 · change: 0.000
Affected products
Weakness classification (CWE)
References
- github.com/nodemailer/nodemailer/security/advisories/GHSA-wmmp-3585-3rmp (vendor-advisory)
- github.com/nodemailer/nodemailer/commit/259c32d (patch)
- github.com/nodemailer/nodemailer/commit/b212ac4 (patch)
- www.vulncheck.com/advisories/nodemailer-before-9.1.0-idn-punycode-domain-allow-… (third-party-advisory)
Frequently asked questions
- What is CVE-2026-92598?
- CVE-2026-92598 is a medium-severity vulnerability in Nodemailer, classified under CWE-436. CVSS score: 6.5/10. Published 2026-09-16.
- How severe is CVE-2026-92598?
- Medium severity. CVSS v3 base score is 6.5 out of 10.