[AH7]

Snyk has created this PR to fix 2 vulnerabilities in the npm dependencies of this project.

Snyk changed the following file(s):

• package.json

Vulnerabilities that will be fixed with an upgrade:

	Issue	Score
	Inefficient Algorithmic Complexity SNYK-JS-NODEMAILER-19651822	721
	Interpretation Conflict SNYK-JS-NODEMAILER-19652370	701

Breaking Change Risk

Notice: This assessment is enhanced by AI.

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[AH7]

This is a major upgrade from version 2.7.2 to 9.1.0, which includes numerous significant breaking changes. A direct upgrade is not feasible and will require substantial code modifications.

Key Breaking Changes:

• Node.js Version Requirement: The required Node.js version has been raised multiple times. Version 3 required Node.js v6+, and newer versions like v9 require Node.js v20 or later.
• Total Rewrite (v3.0): Version 3.0 was a major rewrite from scratch.
  • Templating Removed: All built-in templating features were removed.
  • NTLM Authentication Removed: NTLM authentication support was dropped.
  • OAuth2 Configuration: The configuration for OAuth2 was changed.
  • Zero Dependencies: All dependencies were removed, making it a standalone module.
• API and Transport Changes:
  • SMTP Bundled (v2.0): SMTP support was bundled directly into Nodemailer, removing the need for separate transport plugins.
  • DNS Resolution (v5.0): Changed from dns.lookup() to dns.resolve(), which could affect environments with custom DNS routing.
  • TLS Certificate Validation (v9.0): HTTPS requests for remote content (e.g., attachments, OAuth2) now validate TLS certificates by default. Previously successful requests to servers with self-signed or invalid certificates will now fail.
• TypeScript Migration (v10/future): While the target is v9, it's notable that v10 migrates to TypeScript, which will change type definitions. Users of @types/nodemailer will need to remove it.

Recommendation:

Due to the extensive and cumulative breaking changes across multiple major versions, a simple upgrade is not possible. Treat this as a reimplementation of the email-sending feature.

1. Review Current Implementation: Carefully document how nodemailer@2.7.2 is currently used in your application.
2. Consult v9 Documentation: Refer to the latest Nodemailer documentation to understand the current API for creating transports, configuring authentication (especially OAuth2), and sending mail.
3. Rewrite and Test: Rewrite your email-sending logic using the modern API provided by nodemailer@9.1.0. Pay close attention to Node.js version compatibility and new security features like TLS validation.

Source: Nodemailer CHANGELOG

Notice 🤖: This content was augmented using artificial intelligence. AI-generated content may contain errors and should be reviewed for accuracy before use.