CVE-2026-92598CWE-436

CVE-2026-92598

Medium · published September 17, 2026

CVSS v3.1
6.5
EPSS
0%
Percentile
32.6
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v3.1
6.5 · MEDIUM
Vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:N
CVSS v4.0
8.3 · 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
EPSS
0.00395 · 32.6th percentile
Weakness
CWE-436 · Interpretation Conflict
Published
2026-09-17T02:18Z
References (5)
https://github.com/nodemailer/nodemailer/commit/259c32d · [email protected]https://github.com/nodemailer/nodemailer/commit/b212ac4 · [email protected]https://github.com/nodemailer/nodemailer/security/advisories/GHSA-wmmp-3585-3rmp · [email protected]https://www.vulncheck.com/advisories/nodemailer-before-9.1.0-idn-punycode-domain-allow-list-bypass · [email protected]https://github.com/nodemailer/nodemailer/security/advisories/GHSA-wmmp-3585-3rmp · 134c704f-9b21-4f2e-91b3-4a467353bcc0
EPSS history
Timeline
  • 18 SEP 04:02Z
    EPSS moved — → 0%
    epss
  • 16 SEP 21:47Z
    Nodemailer before 9.1.0 IDN/Punycode Domain Allow-list Bypass
    cvelistv5