What is CVE-2026-82662?

CVE-2026-82662 is a medium-severity vulnerability in Nodemailer, classified under Improper Certificate Validation. CVSS score: 6.5/10. Published 2026-08-31.

How severe is CVE-2026-82662?

Medium severity. CVSS v3 base score is 6.5 out of 10.

Vulnerability in Nodemailer

CVE-2026-82662

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.

Vulnerability class: Improper Certificate Validation

EPSS: 0.001 (2.4th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:N.

Affected products

Nodemailer

Weakness classification (CWE)

CWE-295 — Improper Certificate Validation

References

disclosure@vulncheck.com (vendor-advisory)
disclosure@vulncheck.com (third-party-advisory)

Frequently asked questions

What is CVE-2026-82662?: CVE-2026-82662 is a medium-severity vulnerability in Nodemailer, classified under Improper Certificate Validation. CVSS score: 6.5/10. Published 2026-08-31.
How severe is CVE-2026-82662?: Medium severity. CVSS v3 base score is 6.5 out of 10.