smtp-server/CHANGELOG.md

Create custom SMTP servers on the fly

# Changelog

## [3.18.0](https://github.com/nodemailer/smtp-server/compare/v3.17.1...v3.18.0) (2025-12-22)


### Features

* added support for `allowIPLiteralAddresses` (closes [#244](https://github.com/nodemailer/smtp-server/issues/244)) ([d7e4fa7](https://github.com/nodemailer/smtp-server/commit/d7e4fa7e3597a0416a11528b4b9ac9bd11373306))


### Bug Fixes

* fix literal format checking (closes [#244](https://github.com/nodemailer/smtp-server/issues/244)) ([8b7d426](https://github.com/nodemailer/smtp-server/commit/8b7d4262c34b0923cd81c2e58137facd8b11ae5a))
* fix literal format checking and remove configurable option ([2361c04](https://github.com/nodemailer/smtp-server/commit/2361c04402e75cd8a5c1c2eacd5709b39cdffffc))

## [3.17.1](https://github.com/nodemailer/smtp-server/compare/v3.17.0...v3.17.1) (2025-12-12)


### Bug Fixes

* log tls protocol version and other metainfo on tls error ([#242](https://github.com/nodemailer/smtp-server/issues/242)) ([26a2e3d](https://github.com/nodemailer/smtp-server/commit/26a2e3d7915cf45912c27648b5d130b2e707654c))

## [3.17.0](https://github.com/nodemailer/smtp-server/compare/v3.16.1...v3.17.0) (2025-12-11)


### Features

* add ability to customize auth required error message ([e0f3e64](https://github.com/nodemailer/smtp-server/commit/e0f3e64aa55246aa0ee42d9a6b5303fe2a802226))
* add configurable heloResponse option for HELO/EHLO greeting ([7c8279f](https://github.com/nodemailer/smtp-server/commit/7c8279f4c2ea3d19d27efaa54d8378f12de3f986))
* added DSN capability to feature list (disabled by default) ([#230](https://github.com/nodemailer/smtp-server/issues/230)) ([bb17377](https://github.com/nodemailer/smtp-server/commit/bb17377f47830b1d8ebb414c7c7420b1317b5e0c))
* added support for ENHANCEDSTATUSCODES and DSN (closes [#224](https://github.com/nodemailer/smtp-server/issues/224)) ([#225](https://github.com/nodemailer/smtp-server/issues/225)) ([ad545ef](https://github.com/nodemailer/smtp-server/commit/ad545ef0904b388aa3b98d2156eac5a8e7bfeba0))
* added support for REQUIRETLS and other body params ([71ce3aa](https://github.com/nodemailer/smtp-server/commit/71ce3aae1d0b41709913cb1fa1a89d65f949f92e))


### Bug Fixes

* 193 ([657ac6e](https://github.com/nodemailer/smtp-server/commit/657ac6e9964e5c6613be144450a8a0f61862888c))
* added resolver option, if server closing do not permit commands (fixes [#177](https://github.com/nodemailer/smtp-server/issues/177), fixes [#181](https://github.com/nodemailer/smtp-server/issues/181)) ([#222](https://github.com/nodemailer/smtp-server/issues/222)) ([e79cac9](https://github.com/nodemailer/smtp-server/commit/e79cac9369dbca97cc47a24371151886ea60695e))
* bug with proxy ([#218](https://github.com/nodemailer/smtp-server/issues/218)) ([9515e38](https://github.com/nodemailer/smtp-server/commit/9515e38ae0a2c03a3bbd81e3db9991cb908110d7))
* bumped deps ([c499a3c](https://github.com/nodemailer/smtp-server/commit/c499a3c18e6df6563ac02593f8b053073de5fc84))
* Bumped deps ([ce34da4](https://github.com/nodemailer/smtp-server/commit/ce34da43a76675689bd7a88c75ba6977d2984e21))
* **deploy:** added autorelease ([0dbc8e1](https://github.com/nodemailer/smtp-server/commit/0dbc8e11412982395283b354c90e9ab443a7232a))
* **deps:** Bumped deps ([e096b12](https://github.com/nodemailer/smtp-server/commit/e096b129af13a2c2d4893a8690ba06fe00fe36d2))
* **deps:** Bumped deps ([0a2d601](https://github.com/nodemailer/smtp-server/commit/0a2d6015b69a538b2b615d172b0c5903529370f6))
* **deps:** use punycode module ([438c617](https://github.com/nodemailer/smtp-server/commit/438c617d6ff46121fe76b90da2f1f34220ba7ae4))
* relax email validation to accept Gmail forwarding addresses ([9e83b07](https://github.com/nodemailer/smtp-server/commit/9e83b07be336eec812bd1c6f5f1d4c4389dcb579))
* relax email validation to accept Gmail forwarding addresses ([b5ea6d9](https://github.com/nodemailer/smtp-server/commit/b5ea6d91b1f795ad4ecce47623969ae83e064a63))
* **release:** fixed Git URL on package.json ([5876626](https://github.com/nodemailer/smtp-server/commit/5876626aed6239ff0de4999fdf583febdda38744))
* Replaced punycode with punycode.js ([4ccbcf2](https://github.com/nodemailer/smtp-server/commit/4ccbcf2f7d0daee0554c416be03d0eda7e2999f5))
* strengthen email validation in _parseAddressCommand ([9aced8d](https://github.com/nodemailer/smtp-server/commit/9aced8daa1afdaf40a987ba3e560a7963b910352))
* unref timers to allow graceful process exit ([e2542d2](https://github.com/nodemailer/smtp-server/commit/e2542d292d0ebd6ecae95c6201ab4c6aab496310))
* update dependencies ([7f22889](https://github.com/nodemailer/smtp-server/commit/7f228899744cb9da04e2bff765dab46126b37b09))
* **XFORWARD:** Fixed client hostname processing. Fixes [#147](https://github.com/nodemailer/smtp-server/issues/147) ([d518417](https://github.com/nodemailer/smtp-server/commit/d518417d0b9274cc45a5fde597142f79867d3eeb))

## [3.16.1](https://github.com/nodemailer/smtp-server/compare/smtp-server-v3.16.0...smtp-server-v3.16.1) (2025-11-05)


### Bug Fixes

* relax email validation to accept Gmail forwarding addresses ([b5ea6d9](https://github.com/nodemailer/smtp-server/commit/b5ea6d91b1f795ad4ecce47623969ae83e064a63))

## [3.16.0](https://github.com/nodemailer/smtp-server/compare/smtp-server-v3.15.0...smtp-server-v3.16.0) (2025-10-29)


### Features

* add ability to customize auth required error message ([e0f3e64](https://github.com/nodemailer/smtp-server/commit/e0f3e64aa55246aa0ee42d9a6b5303fe2a802226))
* add configurable heloResponse option for HELO/EHLO greeting ([7c8279f](https://github.com/nodemailer/smtp-server/commit/7c8279f4c2ea3d19d27efaa54d8378f12de3f986))
* added DSN capability to feature list (disabled by default) ([#230](https://github.com/nodemailer/smtp-server/issues/230)) ([bb17377](https://github.com/nodemailer/smtp-server/commit/bb17377f47830b1d8ebb414c7c7420b1317b5e0c))
* added support for ENHANCEDSTATUSCODES and DSN (closes [#224](https://github.com/nodemailer/smtp-server/issues/224)) ([#225](https://github.com/nodemailer/smtp-server/issues/225)) ([ad545ef](https://github.com/nodemailer/smtp-server/commit/ad545ef0904b388aa3b98d2156eac5a8e7bfeba0))
* added support for REQUIRETLS and other body params ([71ce3aa](https://github.com/nodemailer/smtp-server/commit/71ce3aae1d0b41709913cb1fa1a89d65f949f92e))


### Bug Fixes

* 193 ([657ac6e](https://github.com/nodemailer/smtp-server/commit/657ac6e9964e5c6613be144450a8a0f61862888c))
* added resolver option, if server closing do not permit commands (fixes [#177](https://github.com/nodemailer/smtp-server/issues/177), fixes [#181](https://github.com/nodemailer/smtp-server/issues/181)) ([#222](https://github.com/nodemailer/smtp-server/issues/222)) ([e79cac9](https://github.com/nodemailer/smtp-server/commit/e79cac9369dbca97cc47a24371151886ea60695e))
* bug with proxy ([#218](https://github.com/nodemailer/smtp-server/issues/218)) ([9515e38](https://github.com/nodemailer/smtp-server/commit/9515e38ae0a2c03a3bbd81e3db9991cb908110d7))
* bumped deps ([c499a3c](https://github.com/nodemailer/smtp-server/commit/c499a3c18e6df6563ac02593f8b053073de5fc84))
* Bumped deps ([ce34da4](https://github.com/nodemailer/smtp-server/commit/ce34da43a76675689bd7a88c75ba6977d2984e21))
* **deploy:** added autorelease ([0dbc8e1](https://github.com/nodemailer/smtp-server/commit/0dbc8e11412982395283b354c90e9ab443a7232a))
* **deps:** Bumped deps ([e096b12](https://github.com/nodemailer/smtp-server/commit/e096b129af13a2c2d4893a8690ba06fe00fe36d2))
* **deps:** Bumped deps ([0a2d601](https://github.com/nodemailer/smtp-server/commit/0a2d6015b69a538b2b615d172b0c5903529370f6))
* **deps:** use punycode module ([438c617](https://github.com/nodemailer/smtp-server/commit/438c617d6ff46121fe76b90da2f1f34220ba7ae4))
* **release:** fixed Git URL on package.json ([5876626](https://github.com/nodemailer/smtp-server/commit/5876626aed6239ff0de4999fdf583febdda38744))
* Replaced punycode with punycode.js ([4ccbcf2](https://github.com/nodemailer/smtp-server/commit/4ccbcf2f7d0daee0554c416be03d0eda7e2999f5))
* strengthen email validation in _parseAddressCommand ([9aced8d](https://github.com/nodemailer/smtp-server/commit/9aced8daa1afdaf40a987ba3e560a7963b910352))
* unref timers to allow graceful process exit ([e2542d2](https://github.com/nodemailer/smtp-server/commit/e2542d292d0ebd6ecae95c6201ab4c6aab496310))
* **XFORWARD:** Fixed client hostname processing. Fixes [#147](https://github.com/nodemailer/smtp-server/issues/147) ([d518417](https://github.com/nodemailer/smtp-server/commit/d518417d0b9274cc45a5fde597142f79867d3eeb))

## [3.15.0](https://github.com/nodemailer/smtp-server/compare/v3.14.0...v3.15.0) (2025-10-09)


### Features

* added DSN capability to feature list (disabled by default) ([#230](https://github.com/nodemailer/smtp-server/issues/230)) ([bb17377](https://github.com/nodemailer/smtp-server/commit/bb17377f47830b1d8ebb414c7c7420b1317b5e0c))


### Bug Fixes

* bumped deps ([c499a3c](https://github.com/nodemailer/smtp-server/commit/c499a3c18e6df6563ac02593f8b053073de5fc84))

## [3.14.0](https://github.com/nodemailer/smtp-server/compare/v3.13.8...v3.14.0) (2025-06-27)


### Features

* added support for ENHANCEDSTATUSCODES and DSN (closes [#224](https://github.com/nodemailer/smtp-server/issues/224)) ([#225](https://github.com/nodemailer/smtp-server/issues/225)) ([ad545ef](https://github.com/nodemailer/smtp-server/commit/ad545ef0904b388aa3b98d2156eac5a8e7bfeba0))

## [3.13.8](https://github.com/nodemailer/smtp-server/compare/v3.13.7...v3.13.8) (2025-06-04)


### Bug Fixes

* added resolver option, if server closing do not permit commands (fixes [#177](https://github.com/nodemailer/smtp-server/issues/177), fixes [#181](https://github.com/nodemailer/smtp-server/issues/181)) ([#222](https://github.com/nodemailer/smtp-server/issues/222)) ([e79cac9](https://github.com/nodemailer/smtp-server/commit/e79cac9369dbca97cc47a24371151886ea60695e))

## [3.13.7](https://github.com/nodemailer/smtp-server/compare/v3.13.6...v3.13.7) (2025-05-20)


### Bug Fixes

* bug with proxy ([#218](https://github.com/nodemailer/smtp-server/issues/218)) ([9515e38](https://github.com/nodemailer/smtp-server/commit/9515e38ae0a2c03a3bbd81e3db9991cb908110d7))
* Bumped deps ([ce34da4](https://github.com/nodemailer/smtp-server/commit/ce34da43a76675689bd7a88c75ba6977d2984e21))

## [3.13.6](https://github.com/nodemailer/smtp-server/compare/v3.13.5...v3.13.6) (2024-10-21)


### Bug Fixes

* **XFORWARD:** Fixed client hostname processing. Fixes [#147](https://github.com/nodemailer/smtp-server/issues/147) ([d518417](https://github.com/nodemailer/smtp-server/commit/d518417d0b9274cc45a5fde597142f79867d3eeb))

## [3.13.5](https://github.com/nodemailer/smtp-server/compare/v3.13.4...v3.13.5) (2024-09-08)


### Bug Fixes

* Replaced punycode with punycode.js ([4ccbcf2](https://github.com/nodemailer/smtp-server/commit/4ccbcf2f7d0daee0554c416be03d0eda7e2999f5))

## [3.13.4](https://github.com/nodemailer/smtp-server/compare/v3.13.3...v3.13.4) (2024-04-12)


### Bug Fixes

* **deps:** Bumped deps ([e096b12](https://github.com/nodemailer/smtp-server/commit/e096b129af13a2c2d4893a8690ba06fe00fe36d2))

## [3.13.3](https://github.com/nodemailer/smtp-server/compare/v3.13.2...v3.13.3) (2024-02-29)


### Bug Fixes

* **deps:** Bumped deps ([0a2d601](https://github.com/nodemailer/smtp-server/commit/0a2d6015b69a538b2b615d172b0c5903529370f6))

## [3.13.2](https://github.com/nodemailer/smtp-server/compare/v3.13.1...v3.13.2) (2024-02-02)


### Bug Fixes

* **release:** fixed Git URL on package.json ([5876626](https://github.com/nodemailer/smtp-server/commit/5876626aed6239ff0de4999fdf583febdda38744))

## [3.13.1](https://github.com/nodemailer/smtp-server/compare/v3.13.0...v3.13.1) (2024-02-02)


### Bug Fixes

* **deploy:** added autorelease ([0dbc8e1](https://github.com/nodemailer/smtp-server/commit/0dbc8e11412982395283b354c90e9ab443a7232a))
* **deps:** use punycode module ([438c617](https://github.com/nodemailer/smtp-server/commit/438c617d6ff46121fe76b90da2f1f34220ba7ae4))

## v3.13.0 2023-08-15

-   new event handler `onSecure`
-   specified license identifier in package.json (from `MIT` to `MIT-0`)

## v3.12.0 2023-05-24

-   new option `authRequiredMessage`
-   Bumped deps

## v3.11.0 2022-04-28

-   Added github workflow for tests
-   Removed Travis
-   Fixed compatibility for Node v18
-   Bumped deps

## v3.10.0 2022-02-23

-   Add missing space suffix to an empty 334 response
-   Bumped dependencies

## v3.9.0 2021-06-01

-   Bumped dependencies
-   Added extra log entries for 'close' events

## v3.8.0 2020-11-13

-   Bump dependencies to latest
-   Access to challenge and challengeResponse (CRAM-MD5)

## v3.7.0 2020-06-25

-   Bump dependencies to latest

## v3.6.0 2020-03-15

-   Add remote address to any errors
-   Bump dependencies to latest

## v3.5.0 2019-01-04

-   Fix reverse resolving invalid hostname error where greeting was sent twice
-   Bump Nodemailer version to v5.0.0

## v3.4.5 2018-05-25

-   Expose connection id in 'connect' event

## v3.4.4 2018-05-04

-   Enclose punycode calls in try..catch

## v3.4.2 2018-03-16

-   handle missing address in listener handler

## v3.4.0 2017-12-01

-   Added new property `secured` to indicate an TLS server where TLS is handled upstream
-   Allow handling TLS after PROXY header

## v3.3.1 2017-11-28

-   Do not choke on overly long reverse DNS call

## v3.3.0 2017-10-05

-   Added new method updateSecureContext({key, cert}) to update TLS options live

## v3.2.0 2017-10-01

-   Return net.listen() value

## v3.1.0 2017-08-16

-   Added new server option `needsUpgrade` to upgrade sockets to TLS immediately after connection is established. Works with secure: true

## v3.0.0 2017-04-06

-   Reverted license back to MIT

## v2.0.3 2017-02-17

-   Expose `secure` state in session

## v2.0.2 2017-02-17

-   Fixad a bug where `server.onConnect(err)` did not close the connection

## v2.0.1 2017-02-04

-   Fixad a bug where `server.on('connect', data)` had missing `data`

## v2.0.0 2017-02-04

-   Changed license from MIT to EUPL-v1.1
-   Rewrite to use ES6, this means at least Node.js v6.0.0 is required to use smtp-server

## v1.16.1 2016-10-17

-   Allowed rewriting `connect` method

## v1.16.0 2016-10-17

-   Added new method `connect` to pass already established sockets to the server

## v1.15.0 2016-09-23

-   Added new connection property `remotePort`
-   Emit 'connect' event when all handshakes (including PROXY) have been completed

## v1.14.2 2016-09-02

-   Fix issue with invalidly resolved IPv4 addresses on IPv6 interface

## v1.14.1 2016-08-16

-   Ignore connection errors outside transaction

## v1.14.0 2016-08-09

-   Expose connection TLS cipher in the `tlsOptions` property

## v1.13.1 2016-07-29

-   Fixed remoteHostname resolving bug

## v1.13.0 2016-07-29

-   Added new option `disableReverseLookup` to skip reverse resolving client hostname on connection

## v1.12.0 2016-07-25

-   Added new property for session: `session.transmissionType` that identifies the current transmission (SMTP, ESMTP, ESMTPA etc.)

## v1.11.2 2016-07-15

-   Do not strip last linebreak

## v1.11.1 2016-07-12

-   this.server.options bug fix #58 (xpepermint)

## v1.11.0 2016-07-07

-   Added support for LMTP protocol. Set `lmtp` option to `true` in order to use it

## v1.10.0 2016-07-06

-   Added options `hidePIPELINING`, `hide8BITMIME` and `hideSMTPUTF8`

## v1.9.1 2016-04-26

-   Check that `connection._parser` exists before trying to use it in the DATA handler

## v1.9.0 2016-02-20

-   Added new connection method `onClose`
-   Preserve session object, do not re-create it for every transaction
-   Added new server option `allowInsecureAuth`

## v1.8.0-beta.0 2016-01-26

-   Fixed a bug with XCLIENT ADDR validation
-   Added support for XFORWARD command
-   Expose XCLIENT and XFORWARD data for the session object (session.xClient, session.xForward - both are Map objects where uppercase argument name is the key,
    eg. session.xClient.get('ADDR') to see the IP address of XCLIENT)

## v1.7.1 2015-10-27

-   Fixed an issue with empty NAME for XCLIENT

## v1.7.0 2015-10-27

-   Added support for XCLIENT with `useXClient` option
-   Fixed an issue with an empty space after EHLO (67acb1534 by AtlasDev)
-   Added dummy handlers for KILL, WIZ, SHELL

## v1.6.0 2015-09-29

-   Catch errors thrown by dns.reverse on invalid remoteAddress values
-   Added onConnect handler to block unwanted connections (66784aea by jleal52)

## v1.5.2 2015-09-18

-   Fixed regression with node v0.12 where STARTTLS connections were kept hanging around after close

## v1.5.1 2015-09-18

-   Fixed an issue where STARTTLS threw an error
-   Fixed an issue where using unknown auth schemes threw an error (a13f0bc8 by farmdog)

## v1.5.0 2015-08-21

-   Added support for PROXY protocol with `useProxy` option

## v1.4.0 2015-04-30

-   Added support for RFC1870 SIZE extension

## v1.3.1 2015-04-21

-   Added integration tests for CRAM-MD5 authentication
-   Exposed SNI support with `sniOptions` optional server option
-   Define used protocol for NPN as 'smtp'

## v1.3.0 2015-04-21

-   Added CRAM-MD5 authentication support

## v1.2.0 2015-03-11

-   Do not allow HTTP requests. If the client tries to send a command that looks like a HTTP request, then disconnect
-   Close connection after 10 unrecognized commands
-   Close connection after 10 unauthenticated commands
-   Close all pending connections after `server.close()` has been called. Default delay to wait is 30 sec. Can be changed with `closeTimeout` option

## v1.1.1 2015-03-11

-   Fixed an issue with parsing MAIL FROM and RCPT TO commands, if there was a space before or after the first colon

## v1.1.0 2015-03-09

-   Added support for `hideSTARTTLS` option that hides STARTTLS while still allowing to use it (useful for integration test scenarios but not for production use)
-   Changed `logger` option behavior - if the value is `false` then no logging is used. If the value is missing, then output is logged to console
-   Fixed broken examples in the README