---
id: "CVE-2026-121426"
kind: "vulnerability"
aliases: ["CVE-2026-121426"]
title: "Nodemailer: address parser lets mail reach attacker-chosen domains, bypassing allow lists"
severity: "high"
cvss: 8.3
epss: null
exploited: false
status: "open"
category: "package"
products: []
ecosystems: []
tags: ["email", "node", "nodemailer", "package", "self-hosted"]
not_affected_if: ["hardcoded-recipients", "no-user-supplied-addresses"]
published_at: "2026-11-03T15:17:33+00:00"
first_seen_at: "2026-11-03T15:21:59+00:00"
updated_at: "2026-11-03T15:22:40+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-121426", "first_seen_at": "2026-11-03T15:21:59+00:00"}]
---

# Nodemailer: address parser lets mail reach attacker-chosen domains, bypassing allow lists

Nodemailer's addressparser ends an address early at a '>' inside a quoted local part, comment or domain literal. An attacker can submit an address that passes a domain allow list but is delivered to an attacker-controlled domain, exposing message content.

_Summary, check and fix written by a model from the sources; labelled as such._

## How to check

- Check the installed version: `npm ls nodemailer`
- Look for `nodemailer` in package.json and lockfiles at version 3.0.0 up to but not including 10.1.4
- Check whether the app uses recipient allow lists based on address parsing

## Fix

- `nodemailer` `10.1.4` (fixed release, per the NVD description: versions from 3.0.0 before 10.1.4 are affected)

## Timeline

- 2026-11-03T15:21:59+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-121426

## Documents

- [advisory] Vendor advisory: github.com https://github.com/nodemailer/nodemailer/security/advisories/GHSA-85x2-q946-cp5h
- [advisory] Third-party advisory: www.vulncheck.com https://www.vulncheck.com/advisories/nodemailer-3.0.0-before-10.1.4-recipient-domain-confusion-via-addressparser

## From the sources

Nodemailer from 3.0.0 before 10.1.4 contains an address parsing vulnerability in addressparser that ends an angle-addr at a '>' inside a quoted local part, comment or domain literal. Attackers can submit addresses that validate as an allowed domain but are delivered to an attacker-controlled domain, bypassing recipient allow lists and disclosing message content.

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_Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai_