---
id: CVE-2026-100702
title: >-
  Nodemailer before 10.0.2 fails to properly flatten deeply nested arrays in
  recipient fields such as to, cc, and bcc, allowing attackers to cause stack
  exhaustion
summary: >-
  Nodemailer before 10.0.2 fails to properly flatten deeply nested arrays in
  recipient fields such as to, cc, and bcc, allowing attackers to cause stack
  exhaustion. Attackers can supply a deeply nested JSON recipient array that
  triggers re…
severity: medium
cvss: 5.9
cvssVector: 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H'
cwe:
  - CWE-674
  - CWE-770
vendor: nodemailer
product: nodemailer
affected:
  - nodemailer < 10.0.2
published: '2026-09-26'
updated: '2026-09-30'
sourceUpdated: '2026-09-30T16:32:17.940'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-100702'
references:
  - url: >-
      https://github.com/nodemailer/nodemailer/security/advisories/GHSA-8vvx-rff5-p5rq
    label: disclosure@vulncheck.com
  - url: >-
      https://www.vulncheck.com/advisories/nodemailer-before-10.0.2-stack-exhaustion-via-nested-recipient-arrays
    label: disclosure@vulncheck.com
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-100702.json
  - url: 'https://access.redhat.com/security/cve/CVE-2026-100702'
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2541816'
  - url: 'https://www.cve.org/CVERecord?id=CVE-2026-100702'
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-100702'
tags:
  - nvd
  - cve.org
  - csaf
  - vex
  - red-hat
epss: 0.0025
epssPercentile: 0.16276
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-09-26T23:11:09.180121Z'
ingestedAt: '2026-09-26T13:33:20.902Z'
---

## Overview

Nodemailer before 10.0.2 fails to properly flatten deeply nested arrays in recipient fields such as to, cc, and bcc, allowing attackers to cause stack exhaustion. Attackers can supply a deeply nested JSON recipient array that triggers recursive Array.toString() conversion, exhausting the call stack and terminating the Node.js process.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.

## Vendor advisories

- **Red Hat VEX** · Moderate · affected: Red Hat Developer Hub, Red Hat Enterprise Linux 10, Self-service automation portal 2 · no fix planned: Red Hat Developer Hub, Red Hat Enterprise Linux 10, Self-service automation portal 2 · updated 2026-09-26 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-100702.json)