Vulnerability · Published Aug 31, 2026 · Assigned by VulnCheck

CVE-2026-82662Nodemailer before 8.0.8 TLS Certificate Validation Bypass

Medium 6.5

In plain English

A medium-severity improper certificate 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 0.2% (higher than 9% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)6.5Medium

Exploit odds (30 days)0.2%top 91.1% of all CVEs

Exploited in the wildNo reportsCISA SSVC: poc

Attack toolingNoneno public tooling known

Official description

Nodemailer before 8.0.8 disables TLS certificate verification in lib/fetch/index.js through rejectUnauthorized: false, allowing attackers to intercept OAuth2 token requests. Attackers in a machine-in-the-middle position can capture OAuth client secrets, refresh tokens, and access tokens transmitted over compromised HTTPS connections.

Affected packages & fixed versions

Ecosystem	Package	Fixed in	Advisory
Debian:12	node-nodemailer	no fix listed	DEBIAN-CVE-2026-82662
Debian:13	node-nodemailer	no fix listed	DEBIAN-CVE-2026-82662
Debian:14	node-nodemailer	8.0.11+~8.0.1-1	DEBIAN-CVE-2026-82662
Ubuntu:22.04:LTS	node-nodemailer	no fix listed	UBUNTU-CVE-2026-82662
Ubuntu:24.04:LTS	node-nodemailer	no fix listed	UBUNTU-CVE-2026-82662
Ubuntu:26.04:LTS	node-nodemailer	no fix listed	UBUNTU-CVE-2026-82662
npm	nodemailer	8.0.8	GHSA-r7g4-qg5f-qqm2

Affected products (as reported)

Vendor	Product	Versions
nodemailer	nodemailer	0 – before 8.0.8

Weakness: CWE-295 · Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:N

References

GitHub Security Advisory (GHSA-r7g4-qg5f-qqm2) vendor-advisory
VulnCheck Advisory: Nodemailer before 8.0.8 TLS Certificate Validation Bypass third-party-advisory