nodemailer
10.2.1 · 22 Oct 2026MIT-023.7M / weekRepositoryHomepagenpmAtom feed
10.2.1 is the newest release of 10.x.
In short
1 breaking2 new10 fixed
- breaking
Node.js 20 or newer is required. The Node.js 6 syntax compatibility check and the .npmignore file are gone.
Security
12 advisories affect 10.0.0; 10.1.4 fixes them
- HighNodemailer addressparser: O(n^2) on comment-joined addresses enables a remote DoS (reachable via mailparser)GHSA-prgh-xp8r-p3m5 · 30 Sep 2026Fixed in 10.0.5
- HighNodemailer: Quadratic backtracking in the addressparser free-text fallback allows remote denial of serviceGHSA-v53p-9fqp-m79j · 29 Sep 2026Fixed in 10.0.6
- ModerateNodemailer: Quadratic backtracking in SMTP AUTH mechanism detection regexes allows pre-auth remote denial of serviceGHSA-4ffr-jq9g-5ffx · 27 Oct 2026Fixed in 10.0.13
- ModerateNodemailer: RFC 5322 comment inside an angle-bracket address is never strippedGHSA-g73g-hqqh-jr95 · 27 Oct 2026Fixed in 10.0.13
- ModerateNodemailer: Quadratic (O(n^2)) SMTP client reply parsing lets a malicious server or MITM cause a pre-auth remote denial of serviceGHSA-4g23-2xm8-66gc · 27 Oct 2026Fixed in 10.0.10
7 more
- ModerateNodemailer: A nested comment ends early in addressparser, releasing the rest of the comment as a recipientGHSA-8c8m-p3m8-cjg8 · 23 Oct 2026Fixed in 10.1.4
- ModerateNodemailer: A ";" inside a quoted string or comment ends an address group early in addressparser, turning display text into a recipientGHSA-m943-m63m-w62w · 23 Oct 2026Fixed in 10.1.4
- ModerateNodemailer: A ">" inside a quoted local part ends an angle-addr early in addressparser, delivering to a domain the header does not nameGHSA-85x2-q946-cp5h · 23 Oct 2026Fixed in 10.1.4
- ModerateNodemailer: Quadratic (O(n^2)) DKIM header unfolding lets a large folded header cause remote denial of service during signingGHSA-39m8-27wv-hr27 · 22 Oct 2026Fixed in 10.0.10
- ModerateNodemailer: Quoted local-part can produce malformed envelope recipient through RFC 5322 comment parsingGHSA-g57g-f23g-4646 · 29 Sep 2026Fixed in 10.0.9
- ModerateNodemailer: Nested structured recipient arrays bypass the parser depth limit and cause stack exhaustion DoSGHSA-8vvx-rff5-p5rq · 29 Sep 2026Fixed in 10.0.2
- ModerateNodemailer: Process-global DNS cache reuses TLS `servername` across transports, enabling cross-tenant SMTP credential disclosureGHSA-6vj9-mwq6-2f5v · 28 Sep 2026Fixed in 10.0.2
Release note
Breaking changes
- breaking
Node.js 20 or newer is required. The Node.js 6 syntax compatibility check and the .npmignore file are gone.
Features
Keep the @types/nodemailer type layout working
Migrate to TypeScript with ES module and CommonJS builds
Bug Fixes
Apply the other keys of a configuration object next to its url
dkim: canonicalize raw messages the way verifiers do
Keep a transporter assignable to the plain Transporter type
shared: keep a colon in the user name of a connection or proxy url
shared: refuse URL hosts the legacy parser would truncate
shared: resolve hostnames when the runtime has no interface table
smtp-connection: clear the timers of a connection dropped before the greeting
smtp-connection: keep an incomplete server reply out of lastServerResponse
smtp-pool: free the pool slot when the proxy socket can not be opened
well-known: keep nodemailer/lib/well-known/services.json available