Vulnerability · Published Oct 14, 2026 · Assigned by VulnCheck
CVE-2026-110870Nodemailer before 10.0.13 Improper Input Validation via Angle-Bracket Address Comments
Medium 5.3
In plain English
A medium-severity improper input validation in nodemailer from nodemailer. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 19% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
Nodemailer from 3.0.0 before 10.0.13 contains an improper input validation vulnerability in its address parser that fails to strip RFC 5322 comments inside angle-bracket addresses. Attackers can supply recipients like a display name with a parenthesized comment in the domain, so illegal characters reach envelope.to and RCPT TO, causing rejected delivery or parser interpretation conflicts that bypass domain allow-lists.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | node-nodemailer | no fix listed | DEBIAN-CVE-2026-110870 |
| Debian:13 | node-nodemailer | no fix listed | DEBIAN-CVE-2026-110870 |
| Debian:14 | node-nodemailer | 10.0.13+~8.0.2-1 | DEBIAN-CVE-2026-110870 |
| Ubuntu:22.04:LTS | node-nodemailer | no fix listed | UBUNTU-CVE-2026-110870 |
| Ubuntu:24.04:LTS | node-nodemailer | no fix listed | UBUNTU-CVE-2026-110870 |
| Ubuntu:26.04:LTS | node-nodemailer | no fix listed | UBUNTU-CVE-2026-110870 |
| Ubuntu:26.10 | node-nodemailer | no fix listed | UBUNTU-CVE-2026-110870 |
| npm | nodemailer | 10.0.13 | GHSA-g73g-hqqh-jr95 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| nodemailer | nodemailer | 3.0.0 – before 10.0.13 |
Weakness: CWE-20 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N