# Unreleased Changes
## 🚀 Improvements
- Improve HTML structure in `res.redirect()` responses when HTML format is accepted by adding ``, `
`, and `` tags for better browser compatibility - by [@Bernice55231](https://github.com/Bernice55231) in [#5167](https://github.com/expressjs/express/pull/5167)
5.2.1 / 2025-12-01
=======================
* Revert security fix for [CVE-2024-51999](https://www.cve.org/CVERecord?id=CVE-2024-51999) ([GHSA-pj86-cfqh-vqx6](https://github.com/expressjs/express/security/advisories/GHSA-pj86-cfqh-vqx6))
* The prior release (5.2.0) included an erroneous breaking change related to the extended query parser. There is no actual security vulnerability associated with this behavior (CVE-2024-51999 has been rejected). The change has been fully reverted in this release.
5.2.0 / 2025-12-01
========================
* Security fix for [CVE-2024-51999](https://www.cve.org/CVERecord?id=CVE-2024-51999) ([GHSA-pj86-cfqh-vqx6](https://github.com/expressjs/express/security/advisories/GHSA-pj86-cfqh-vqx6))
* deps: `body-parser@^2.2.1`
* A deprecation warning was added when using `res.redirect` with undefined arguments, Express now emits a warning to help detect calls that pass undefined as the status or URL and make them easier to fix.
5.1.0 / 2025-03-31
========================
* Add support for `Uint8Array` in `res.send()`
* Add support for ETag option in `res.sendFile()`
* Add support for multiple links with the same rel in `res.links()`
* Add funding field to package.json
* perf: use loop for acceptParams
* refactor: prefix built-in node module imports
* deps: remove `setprototypeof`
* deps: remove `safe-buffer`
* deps: remove `utils-merge`
* deps: remove `methods`
* deps: remove `depd`
* deps: `debug@^4.4.0`
* deps: `body-parser@^2.2.0`
* deps: `router@^2.2.0`
* deps: `content-type@^1.0.5`
* deps: `finalhandler@^2.1.0`
* deps: `qs@^6.14.0`
* deps: `server-static@2.2.0`
* deps: `type-is@2.0.1`
5.0.1 / 2024-10-08
==========
* Update `cookie` semver lock to address [CVE-2024-47764](https://nvd.nist.gov/vuln/detail/CVE-2024-47764)
5.0.0 / 2024-09-10
=========================
* remove:
- `path-is-absolute` dependency - use `path.isAbsolute` instead
* breaking:
* `res.status()` accepts only integers, and input must be greater than 99 and less than 1000
* will throw a `RangeError: Invalid status code: ${code}. Status code must be greater than 99 and less than 1000.` for inputs outside this range
* will throw a `TypeError: Invalid status code: ${code}. Status code must be an integer.` for non integer inputs
* deps: send@1.0.0
* `res.redirect('back')` and `res.location('back')` is no longer a supported magic string, explicitly use `req.get('Referrer') || '/'`.
* change:
- `res.clearCookie` will ignore user provided `maxAge` and `expires` options
* deps: cookie-signature@^1.2.1
* deps: debug@4.3.6
* deps: merge-descriptors@^2.0.0
* deps: serve-static@^2.1.0
* deps: qs@6.13.0
* deps: accepts@^2.0.0
* deps: mime-types@^3.0.0
- `application/javascript` => `text/javascript`
* deps: type-is@^2.0.0
* deps: content-disposition@^1.0.0
* deps: finalhandler@^2.0.0
* deps: fresh@^2.0.0
* deps: body-parser@^2.0.1
* deps: send@^1.1.0
5.0.0-beta.3 / 2024-03-25
=========================
This incorporates all changes after 4.19.1 up to 4.19.2.
5.0.0-beta.2 / 2024-03-20
=========================
This incorporates all changes after 4.17.2 up to 4.19.1.
5.0.0-beta.1 / 2022-02-14
=========================
This is the first Express 5.0 beta release, based off 4.17.2 and includes
changes from 5.0.0-alpha.8.
* change:
- Default "query parser" setting to `'simple'`
- Requires Node.js 4+
- Use `mime-types` for file to content type mapping
* deps: array-flatten@3.0.0
* deps: body-parser@2.0.0-beta.1
- `req.body` is no longer always initialized to `{}`
- `urlencoded` parser now defaults `extended` to `false`
- Use `on-finished` to determine when body read
* deps: router@2.0.0-beta.1
- Add new `?`, `*`, and `+` parameter modifiers
- Internalize private `router.process_params` method
- Matching group expressions are only RegExp syntax
- Named matching groups no longer available by position in `req.params`
- Regular expressions can only be used in a matching group
- Remove `debug` dependency
- Special `*` path segment behavior removed
- deps: array-flatten@3.0.0
- deps: parseurl@~1.3.3
- deps: path-to-regexp@3.2.0
- deps: setprototypeof@1.2.0
* deps: send@1.0.0-beta.1
- Change `dotfiles` option default to `'ignore'`
- Remove `hidden` option; use `dotfiles` option instead
- Use `mime-types` for file to content type mapping
- deps: debug@3.1.0
* deps: serve-static@2.0.0-beta.1
- Change `dotfiles` option default to `'ignore'`
- Remove `hidden` option; use `dotfiles` option instead
- Use `mime-types` for file to content type mapping
- Remove `express.static.mime` export; use `mime-types` package instead
- deps: send@1.0.0-beta.1
5.0.0-alpha.8 / 2020-03-25
==========================
This is the eighth Express 5.0 alpha release, based off 4.17.1 and includes
changes from 5.0.0-alpha.7.
5.0.0-alpha.7 / 2018-10-26
==========================
This is the seventh Express 5.0 alpha release, based off 4.16.4 and includes
changes from 5.0.0-alpha.6.
The major change with this alpha is the basic support for returned, rejected
Promises in the router.
* remove:
- `path-to-regexp` dependency
* deps: debug@3.1.0
- Add `DEBUG_HIDE_DATE` environment variable
- Change timer to per-namespace instead of global
- Change non-TTY date format
- Remove `DEBUG_FD` environment variable support
- Support 256 namespace colors
* deps: router@2.0.0-alpha.1
- Add basic support for returned, rejected Promises
- Fix JSDoc for `Router` constructor
- deps: debug@3.1.0
- deps: parseurl@~1.3.2
- deps: setprototypeof@1.1.0
- deps: utils-merge@1.0.1
5.0.0-alpha.6 / 2017-09-24
==========================
This is the sixth Express 5.0 alpha release, based off 4.15.5 and includes
changes from 5.0.0-alpha.5.
* remove:
- `res.redirect(url, status)` signature - use `res.redirect(status, url)`
- `res.send(status, body)` signature - use `res.status(status).send(body)`
* deps: router@~1.3.1
- deps: debug@2.6.8
5.0.0-alpha.5 / 2017-03-06
==========================
This is the fifth Express 5.0 alpha release, based off 4.15.2 and includes
changes from 5.0.0-alpha.4.
5.0.0-alpha.4 / 2017-03-01
==========================
This is the fourth Express 5.0 alpha release, based off 4.15.0 and includes
changes from 5.0.0-alpha.3.
* remove:
- Remove Express 3.x middleware error stubs
* deps: router@~1.3.0
- Add `next("router")` to exit from router
- Fix case where `router.use` skipped requests routes did not
- Skip routing when `req.url` is not set
- Use `%o` in path debug to tell types apart
- deps: debug@2.6.1
- deps: setprototypeof@1.0.3
- perf: add fast match path for `*` route
5.0.0-alpha.3 / 2017-01-28
==========================
This is the third Express 5.0 alpha release, based off 4.14.1 and includes
changes from 5.0.0-alpha.2.
* remove:
- `res.json(status, obj)` signature - use `res.status(status).json(obj)`
- `res.jsonp(status, obj)` signature - use `res.status(status).jsonp(obj)`
- `res.vary()` (no arguments) -- provide a field name as an argument
* deps: array-flatten@2.1.1
* deps: path-is-absolute@1.0.1
* deps: router@~1.1.5
- deps: array-flatten@2.0.1
- deps: methods@~1.1.2
- deps: parseurl@~1.3.1
- deps: setprototypeof@1.0.2
5.0.0-alpha.2 / 2015-07-06
==========================
This is the second Express 5.0 alpha release, based off 4.13.1 and includes
changes from 5.0.0-alpha.1.
* remove:
- `app.param(fn)`
- `req.param()` -- use `req.params`, `req.body`, or `req.query` instead
* change:
- `res.render` callback is always async, even for sync view engines
- The leading `:` character in `name` for `app.param(name, fn)` is no longer removed
- Use `router` module for routing
- Use `path-is-absolute` module for absolute path detection
5.0.0-alpha.1 / 2014-11-06
==========================
This is the first Express 5.0 alpha release, based off 4.10.1.
* remove:
- `app.del` - use `app.delete`
- `req.acceptsCharset` - use `req.acceptsCharsets`
- `req.acceptsEncoding` - use `req.acceptsEncodings`
- `req.acceptsLanguage` - use `req.acceptsLanguages`
- `res.json(obj, status)` signature - use `res.json(status, obj)`
- `res.jsonp(obj, status)` signature - use `res.jsonp(status, obj)`
- `res.send(body, status)` signature - use `res.send(status, body)`
- `res.send(status)` signature - use `res.sendStatus(status)`
- `res.sendfile` - use `res.sendFile` instead
- `express.query` middleware
* change:
- `req.host` now returns host (`hostname:port`) - use `req.hostname` for only hostname
- `req.query` is now a getter instead of a plain property
* add:
- `app.router` is a reference to the base router
4.20.0 / 2024-09-10
==========
* deps: serve-static@0.16.0
* Remove link renderization in html while redirecting
* deps: send@0.19.0
* Remove link renderization in html while redirecting
* deps: body-parser@0.6.0
* add `depth` option to customize the depth level in the parser
* IMPORTANT: The default `depth` level for parsing URL-encoded data is now `32` (previously was `Infinity`)
* Remove link renderization in html while using `res.redirect`
* deps: path-to-regexp@0.1.10
- Adds support for named matching groups in the routes using a regex
- Adds backtracking protection to parameters without regexes defined
* deps: encodeurl@~2.0.0
- Removes encoding of `\`, `|`, and `^` to align better with URL spec
* Deprecate passing `options.maxAge` and `options.expires` to `res.clearCookie`
- Will be ignored in v5, clearCookie will set a cookie with an expires in the past to instruct clients to delete the cookie
4.19.2 / 2024-03-25
==========
* Improved fix for open redirect allow list bypass
4.19.1 / 2024-03-20
==========
* Allow passing non-strings to res.location with new encoding handling checks
4.19.0 / 2024-03-20
==========
* Prevent open redirect allow list bypass due to encodeurl
* deps: cookie@0.6.0
4.18.3 / 2024-02-29
==========
* Fix routing requests without method
* deps: body-parser@1.20.2
- Fix strict json error message on Node.js 19+
- deps: content-type@~1.0.5
- deps: raw-body@2.5.2
* deps: cookie@0.6.0
- Add `partitioned` option
4.18.2 / 2022-10-08
===================
* Fix regression routing a large stack in a single route
* deps: body-parser@1.20.1
- deps: qs@6.11.0
- perf: remove unnecessary object clone
* deps: qs@6.11.0
4.18.1 / 2022-04-29
===================
* Fix hanging on large stack of sync routes
4.18.0 / 2022-04-25
===================
* Add "root" option to `res.download`
* Allow `options` without `filename` in `res.download`
* Deprecate string and non-integer arguments to `res.status`
* Fix behavior of `null`/`undefined` as `maxAge` in `res.cookie`
* Fix handling very large stacks of sync middleware
* Ignore `Object.prototype` values in settings through `app.set`/`app.get`
* Invoke `default` with same arguments as types in `res.format`
* Support proper 205 responses using `res.send`
* Use `http-errors` for `res.format` error
* deps: body-parser@1.20.0
- Fix error message for json parse whitespace in `strict`
- Fix internal error when inflated body exceeds limit
- Prevent loss of async hooks context
- Prevent hanging when request already read
- deps: depd@2.0.0
- deps: http-errors@2.0.0
- deps: on-finished@2.4.1
- deps: qs@6.10.3
- deps: raw-body@2.5.1
* deps: cookie@0.5.0
- Add `priority` option
- Fix `expires` option to reject invalid dates
* deps: depd@2.0.0
- Replace internal `eval` usage with `Function` constructor
- Use instance methods on `process` to check for listeners
* deps: finalhandler@1.2.0
- Remove set content headers that break response
- deps: on-finished@2.4.1
- deps: statuses@2.0.1
* deps: on-finished@2.4.1
- Prevent loss of async hooks context
* deps: qs@6.10.3
* deps: send@0.18.0
- Fix emitted 416 error missing headers property
- Limit the headers removed for 304 response
- deps: depd@2.0.0
- deps: destroy@1.2.0
- deps: http-errors@2.0.0
- deps: on-finished@2.4.1
- deps: statuses@2.0.1
* deps: serve-static@1.15.0
- deps: send@0.18.0
* deps: statuses@2.0.1
- Remove code 306
- Rename `425 Unordered Collection` to standard `425 Too Early`
4.17.3 / 2022-02-16
===================
* deps: accepts@~1.3.8
- deps: mime-types@~2.1.34
- deps: negotiator@0.6.3
* deps: body-parser@1.19.2
- deps: bytes@3.1.2
- deps: qs@6.9.7
- deps: raw-body@2.4.3
* deps: cookie@0.4.2
* deps: qs@6.9.7
* Fix handling of `__proto__` keys
* pref: remove unnecessary regexp for trust proxy
4.17.2 / 2021-12-16
===================
* Fix handling of `undefined` in `res.jsonp`
* Fix handling of `undefined` when `"json escape"` is enabled
* Fix incorrect middleware execution with unanchored `RegExp`s
* Fix `res.jsonp(obj, status)` deprecation message
* Fix typo in `res.is` JSDoc
* deps: body-parser@1.19.1
- deps: bytes@3.1.1
- deps: http-errors@1.8.1
- deps: qs@6.9.6
- deps: raw-body@2.4.2
- deps: safe-buffer@5.2.1
- deps: type-is@~1.6.18
* deps: content-disposition@0.5.4
- deps: safe-buffer@5.2.1
* deps: cookie@0.4.1
- Fix `maxAge` option to reject invalid values
* deps: proxy-addr@~2.0.7
- Use `req.socket` over deprecated `req.connection`
- deps: forwarded@0.2.0
- deps: ipaddr.js@1.9.1
* deps: qs@6.9.6
* deps: safe-buffer@5.2.1
* deps: send@0.17.2
- deps: http-errors@1.8.1
- deps: ms@2.1.3
- pref: ignore empty http tokens
* deps: serve-static@1.14.2
- deps: send@0.17.2
* deps: setprototypeof@1.2.0
4.17.1 / 2019-05-25
===================
* Revert "Improve error message for `null`/`undefined` to `res.status`"
4.17.0 / 2019-05-16
===================
* Add `express.raw` to parse bodies into `Buffer`
* Add `express.text` to parse bodies into string
* Improve error message for non-strings to `res.sendFile`
* Improve error message for `null`/`undefined` to `res.status`
* Support multiple hosts in `X-Forwarded-Host`
* deps: accepts@~1.3.7
* deps: body-parser@1.19.0
- Add encoding MIK
- Add petabyte (`pb`) support
- Fix parsing array brackets after index
- deps: bytes@3.1.0
- deps: http-errors@1.7.2
- deps: iconv-lite@0.4.24
- deps: qs@6.7.0
- deps: raw-body@2.4.0
- deps: type-is@~1.6.17
* deps: content-disposition@0.5.3
* deps: cookie@0.4.0
- Add `SameSite=None` support
* deps: finalhandler@~1.1.2
- Set stricter `Content-Security-Policy` header
- deps: parseurl@~1.3.3
- deps: statuses@~1.5.0
* deps: parseurl@~1.3.3
* deps: proxy-addr@~2.0.5
- deps: ipaddr.js@1.9.0
* deps: qs@6.7.0
- Fix parsing array brackets after index
* deps: range-parser@~1.2.1
* deps: send@0.17.1
- Set stricter CSP header in redirect & error responses
- deps: http-errors@~1.7.2
- deps: mime@1.6.0
- deps: ms@2.1.1
- deps: range-parser@~1.2.1
- deps: statuses@~1.5.0
- perf: remove redundant `path.normalize` call
* deps: serve-static@1.14.1
- Set stricter CSP header in redirect response
- deps: parseurl@~1.3.3
- deps: send@0.17.1
* deps: setprototypeof@1.1.1
* deps: statuses@~1.5.0
- Add `103 Early Hints`
* deps: type-is@~1.6.18
- deps: mime-types@~2.1.24
- perf: prevent internal `throw` on invalid type
4.16.4 / 2018-10-10
===================
* Fix issue where `"Request aborted"` may be logged in `res.sendfile`
* Fix JSDoc for `Router` constructor
* deps: body-parser@1.18.3
- Fix deprecation warnings on Node.js 10+
- Fix stack trace for strict json parse error
- deps: depd@~1.1.2
- deps: http-errors@~1.6.3
- deps: iconv-lite@0.4.23
- deps: qs@6.5.2
- deps: raw-body@2.3.3
- deps: type-is@~1.6.16
* deps: proxy-addr@~2.0.4
- deps: ipaddr.js@1.8.0
* deps: qs@6.5.2
* deps: safe-buffer@5.1.2
4.16.3 / 2018-03-12
===================
* deps: accepts@~1.3.5
- deps: mime-types@~2.1.18
* deps: depd@~1.1.2
- perf: remove argument reassignment
* deps: encodeurl@~1.0.2
- Fix encoding `%` as last character
* deps: finalhandler@1.1.1
- Fix 404 output for bad / missing pathnames
- deps: encodeurl@~1.0.2
- deps: statuses@~1.4.0
* deps: proxy-addr@~2.0.3
- deps: ipaddr.js@1.6.0
* deps: send@0.16.2
- Fix incorrect end tag in default error & redirects
- deps: depd@~1.1.2
- deps: encodeurl@~1.0.2
- deps: statuses@~1.4.0
* deps: serve-static@1.13.2
- Fix incorrect end tag in redirects
- deps: encodeurl@~1.0.2
- deps: send@0.16.2
* deps: statuses@~1.4.0
* deps: type-is@~1.6.16
- deps: mime-types@~2.1.18
4.16.2 / 2017-10-09
===================
* Fix `TypeError` in `res.send` when given `Buffer` and `ETag` header set
* perf: skip parsing of entire `X-Forwarded-Proto` header
4.16.1 / 2017-09-29
===================
* deps: send@0.16.1
* deps: serve-static@1.13.1
- Fix regression when `root` is incorrectly set to a file
- deps: send@0.16.1
4.16.0 / 2017-09-28
===================
* Add `"json escape"` setting for `res.json` and `res.jsonp`
* Add `express.json` and `express.urlencoded` to parse bodies
* Add `options` argument to `res.download`
* Improve error message when autoloading invalid view engine
* Improve error messages when non-function provided as middleware
* Skip `Buffer` encoding when not generating ETag for small response
* Use `safe-buffer` for improved Buffer API
* deps: accepts@~1.3.4
- deps: mime-types@~2.1.16
* deps: content-type@~1.0.4
- perf: remove argument reassignment
- perf: skip parameter parsing when no parameters
* deps: etag@~1.8.1
- perf: replace regular expression with substring
* deps: finalhandler@1.1.0
- Use `res.headersSent` when available
* deps: parseurl@~1.3.2
- perf: reduce overhead for full URLs
- perf: unroll the "fast-path" `RegExp`
* deps: proxy-addr@~2.0.2
- Fix trimming leading / trailing OWS in `X-Forwarded-For`
- deps: forwarded@~0.1.2
- deps: ipaddr.js@1.5.2
- perf: reduce overhead when no `X-Forwarded-For` header
* deps: qs@6.5.1
- Fix parsing & compacting very deep objects
* deps: send@0.16.0
- Add 70 new types for file extensions
- Add `immutable` option
- Fix missing `` in default error & redirects
- Set charset as "UTF-8" for .js and .json
- Use instance methods on steam to check for listeners
- deps: mime@1.4.1
- perf: improve path validation speed
* deps: serve-static@1.13.0
- Add 70 new types for file extensions
- Add `immutable` option
- Set charset as "UTF-8" for .js and .json
- deps: send@0.16.0
* deps: setprototypeof@1.1.0
* deps: utils-merge@1.0.1
* deps: vary@~1.1.2
- perf: improve header token parsing speed
* perf: re-use options object when generating ETags
* perf: remove dead `.charset` set in `res.jsonp`
4.15.5 / 2017-09-24
===================
* deps: debug@2.6.9
* deps: finalhandler@~1.0.6
- deps: debug@2.6.9
- deps: parseurl@~1.3.2
* deps: fresh@0.5.2
- Fix handling of modified headers with invalid dates
- perf: improve ETag match loop
- perf: improve `If-None-Match` token parsing
* deps: send@0.15.6
- Fix handling of modified headers with invalid dates
- deps: debug@2.6.9
- deps: etag@~1.8.1
- deps: fresh@0.5.2
- perf: improve `If-Match` token parsing
* deps: serve-static@1.12.6
- deps: parseurl@~1.3.2
- deps: send@0.15.6
- perf: improve slash collapsing
4.15.4 / 2017-08-06
===================
* deps: debug@2.6.8
* deps: depd@~1.1.1
- Remove unnecessary `Buffer` loading
* deps: finalhandler@~1.0.4
- deps: debug@2.6.8
* deps: proxy-addr@~1.1.5
- Fix array argument being altered
- deps: ipaddr.js@1.4.0
* deps: qs@6.5.0
* deps: send@0.15.4
- deps: debug@2.6.8
- deps: depd@~1.1.1
- deps: http-errors@~1.6.2
* deps: serve-static@1.12.4
- deps: send@0.15.4
4.15.3 / 2017-05-16
===================
* Fix error when `res.set` cannot add charset to `Content-Type`
* deps: debug@2.6.7
- Fix `DEBUG_MAX_ARRAY_LENGTH`
- deps: ms@2.0.0
* deps: finalhandler@~1.0.3
- Fix missing `