---
id: CVE-2026-92596
title: >-
  Nodemailer before 9.1.0 contains a quadratic time complexity vulnerability in
  the addressparser component that allows remote attackers to cause denial of
  service by supplying a crafted comma-separated address list
summary: >-
  Nodemailer before 9.1.0 contains a quadratic time complexity vulnerability in
  the addressparser component that allows remote attackers to cause denial of
  service by supplying a crafted comma-separated address list. Attackers can
  send a s…
severity: high
cvss: 7.5
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'
cwe:
  - CWE-400
  - CWE-1050
vendor: nodemailer
product: nodemailer
affected:
  - nodemailer < 9.1.0
published: '2026-09-16'
updated: '2026-09-22'
sourceUpdated: '2026-09-22T20:25:55.870'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-92596'
references:
  - url: 'https://github.com/nodemailer/nodemailer/commit/34da642'
    label: disclosure@vulncheck.com
  - url: 'https://github.com/nodemailer/nodemailer/commit/7cc38af'
    label: disclosure@vulncheck.com
  - url: 'https://github.com/nodemailer/nodemailer/commit/83b8c48'
    label: disclosure@vulncheck.com
  - url: 'https://github.com/nodemailer/nodemailer/commit/9116da9'
    label: disclosure@vulncheck.com
  - url: >-
      https://github.com/nodemailer/nodemailer/security/advisories/GHSA-2x7j-588g-ccc2
    label: disclosure@vulncheck.com
  - url: >-
      https://www.vulncheck.com/advisories/nodemailer-before-9.1.0-denial-of-service-via-addressparser
    label: disclosure@vulncheck.com
  - url: >-
      https://github.com/nodemailer/nodemailer/security/advisories/GHSA-2x7j-588g-ccc2
    label: 134c704f-9b21-4f2e-91b3-4a467353bcc0
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-92596.json
  - url: 'https://access.redhat.com/security/cve/CVE-2026-92596'
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2536015'
  - url: 'https://www.cve.org/CVERecord?id=CVE-2026-92596'
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-92596'
tags:
  - nvd
  - cve.org
  - exploit-available
  - csaf
  - vex
  - red-hat
epss: 0.00824
epssPercentile: 0.55578
exploitAvailable: true
ssvc:
  exploitation: poc
  automatable: 'yes'
  technicalImpact: partial
  timestamp: '2026-09-17T13:23:08.515673Z'
ingestedAt: '2026-09-16T22:06:50.927Z'
---

## Overview

Nodemailer before 9.1.0 contains a quadratic time complexity vulnerability in the addressparser component that allows remote attackers to cause denial of service by supplying a crafted comma-separated address list. Attackers can send a single email with a large number of addresses to block the Node.js event loop for extended periods, consuming 100% CPU and freezing the process.

## Remediation

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

## Vendor advisories

- **Red Hat VEX** · Important · affected: Self-service automation portal 2 · no fix planned: Self-service automation portal 2 · updated 2026-09-25 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-92596.json)