Improper Certificate Validation in nodemailer - CVE-2026-82662
Published: May 27, 2026 / Updated: September 14, 2026
Vulnerability identifier: #VU132359
CSH Severity: Medium
CVSS v4: 8.3 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-82662
CWE-ID: CWE-295
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to disclose sensitive OAuth credentials.
The vulnerability exists due to improper certificate validation in the internal HTTPS fetch client in lib/fetch/index.js when retrieving OAuth2 tokens over HTTPS. A remote attacker can perform a machine-in-the-middle attack using an invalid or self-signed certificate to disclose sensitive OAuth credentials.
The issue affects OAuth2 token requests and related outbound HTTPS requests that use the internal fetch implementation.
Affected software
nodemailer
How to mitigate CVE-2026-82662
Install security update from vendor's website.
nodemailer - update to 8.0.8