Vulnerability · Published Oct 14, 2026 · Assigned by VulnCheck
CVE-2026-110872Nodemailer 3.0.0 before 10.0.10 Denial of Service via SMTP Reply Parsing
Medium 5.9
In plain English
A medium-severity uncontrolled resource consumption in nodemailer from nodemailer. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 29% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
Nodemailer from 3.0.0 before 10.0.10 contains a quadratic complexity denial of service vulnerability in the SMTP client reply parser in SMTPConnection._onData and isPartialResponse. A malicious SMTP server or on-path attacker can stream continuation lines without a completion line before authentication, blocking the Node.js event loop and exhausting memory.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | node-nodemailer | no fix listed | DEBIAN-CVE-2026-110872 |
| Debian:13 | node-nodemailer | no fix listed | DEBIAN-CVE-2026-110872 |
| Debian:14 | node-nodemailer | 10.0.10+~8.0.1-1 | DEBIAN-CVE-2026-110872 |
| Ubuntu:22.04:LTS | node-nodemailer | no fix listed | UBUNTU-CVE-2026-110872 |
| Ubuntu:24.04:LTS | node-nodemailer | no fix listed | UBUNTU-CVE-2026-110872 |
| Ubuntu:26.04:LTS | node-nodemailer | no fix listed | UBUNTU-CVE-2026-110872 |
| Ubuntu:26.10 | node-nodemailer | no fix listed | UBUNTU-CVE-2026-110872 |
| npm | nodemailer | 10.0.10 | GHSA-4g23-2xm8-66gc |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| nodemailer | nodemailer | 3.0.0 – before 10.0.10 |
Weakness: CWE-400 · Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
References
- GitHub Security Advisory (GHSA-4g23-2xm8-66gc) vendor-advisory
- VulnCheck Advisory: Nodemailer 3.0.0 before 10.0.10 Denial of Service via SMTP Reply Parsing third-party-advisory