Improper Certificate Validation in nodemailer - CVE-2026-100701
Published: September 30, 2026
Vulnerability identifier: #VU153014
CSH Severity: Low
CVSS v4: 6 [CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-100701
CWE-ID: CWE-295
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote user to disclose SMTP credentials.
The vulnerability exists due to improper certificate validation in the process-global DNS cache and TLS connection option resolution when processing direct SMTPS connections that share a non-IP host while using different TLS server names. A remote user can prime the DNS cache with an attacker-controlled TLS server name to disclose SMTP credentials.
The default DNS cache lifetime is five minutes.
Affected software
nodemailer
How to mitigate CVE-2026-100701
Install security update from vendor's website.
nodemailer - update to 10.0.2