Express version 3.18.3 represents a minor update over its predecessor, 3.18.2, within the popular web development framework inspired by Sinatra. While the core functionality remains consistent, subtle refinements and dependency adjustments characterize this release. A notable distinction lies in the "connect" dependency, which advances from version 2.27.2 in 3.18.2 to 2.27.3 in 3.18.3, suggesting potential bug fixes or minor feature enhancements within the Connect middleware layer.
Furthermore, the "should" dev dependency experiences an upgrade from version 4.1.0 to 4.2.1. These changes in dev dependencies often signal improvements in the testing or development workflow, providing developers with more robust tools for quality assurance.
Developers adopting Express should consider these minor version bumps as opportunities to leverage the latest refinements and enhancements. While major API changes are unlikely in such incremental updates, staying current ensures access to the most stable and reliable code base. Examining the release notes for Connect version 2.27.3 can provide more specific insights into its changes and possible benefits for existing Express applications. The Express framework continues to provide a solid foundation for building web applications and APIs.
All the vulnerabilities related to the version 3.18.3 of the package
Express ressource injection
A vulnerability has been identified in the Express response.links function, allowing for arbitrary resource injection in the Link header when unsanitized data is used.
The issue arises from improper sanitization in Link header values, which can allow a combination of characters like ,, ;, and <> to preload malicious resources.
This vulnerability is especially relevant for dynamic parameters.
Express Open Redirect vulnerability
URL Redirection to Untrusted Site ('Open Redirect') vulnerability in Express. This vulnerability affects the use of the Express Response object. This issue impacts Express: from 3.4.5 before 4.0.0-rc1.
Express.js Open Redirect in malformed URLs
Versions of Express.js prior to 4.19.2 and pre-release alpha and beta versions before 5.0.0-beta.3 are affected by an open redirect vulnerability using malformed URLs.
When a user of Express performs a redirect using a user-provided URL Express performs an encode using encodeurl on the contents before passing it to the location header. This can cause malformed URLs to be evaluated in unexpected ways by common redirect allow list implementations in Express applications, leading to an Open Redirect via bypass of a properly implemented allow list.
The main method impacted is res.location() but this is also called from within res.redirect().
https://github.com/expressjs/express/commit/0867302ddbde0e9463d0564fea5861feb708c2dd https://github.com/expressjs/express/commit/0b746953c4bd8e377123527db11f9cd866e39f94
An initial fix went out with express@4.19.0, we then patched a feature regression in 4.19.1 and added improved handling for the bypass in 4.19.2.
The fix for this involves pre-parsing the url string with either require('node:url').parse or new URL. These are steps you can take on your own before passing the user input string to res.location or res.redirect.
https://github.com/expressjs/express/pull/5539 https://github.com/koajs/koa/issues/1800 https://expressjs.com/en/4x/api.html#res.location
express vulnerable to XSS via response.redirect()
In express <4.20.0, passing untrusted user input - even after sanitizing it - to response.redirect() may execute untrusted code
this issue is patched in express 4.20.0
users are encouraged to upgrade to the patched version of express, but otherwise can workaround this issue by making sure any untrusted inputs are safe, ideally by validating them against an explicit allowlist
successful exploitation of this vector requires the following:
Root Path Disclosure in send
Versions of send prior to 0.11.2 are affected by an information leakage vulnerability which may allow an attacker to enumerate paths on the server filesystem.
Update to version 0.11.1 or later.
send vulnerable to template injection that can lead to XSS
passing untrusted user input - even after sanitizing it - to SendStream.redirect() may execute untrusted code
this issue is patched in send 0.19.0
users are encouraged to upgrade to the patched version of express, but otherwise can workaround this issue by making sure any untrusted inputs are safe, ideally by validating them against an explicit allowlist
successful exploitation of this vector requires the following:
Regular Expression Denial of Service in ms
Versions of ms prior to 0.7.1 are affected by a regular expression denial of service vulnerability when extremely long version strings are parsed.
var ms = require('ms');
var genstr = function (len, chr) {
var result = "";
for (i=0; i<=len; i++) {
result = result + chr;
}
return result;
}
ms(genstr(process.argv[2], "5") + " minutea");
Showing increase in execution time based on the input string.
$ time node ms.js 10000
real 0m0.758s
user 0m0.724s
sys 0m0.031s
$ time node ms.js 20000
real 0m2.580s
user 0m2.494s
sys 0m0.047s
$ time node ms.js 30000
real 0m5.747s
user 0m5.483s
sys 0m0.080s
$ time node ms.js 80000
real 0m41.022s
user 0m38.894s
sys 0m0.529s
Vercel ms Inefficient Regular Expression Complexity vulnerability
A vulnerability, which was classified as problematic, has been found in vercel ms up to 1.x. This issue affects the function parse of the file index.js. The manipulation of the argument str leads to inefficient regular expression complexity. The attack may be initiated remotely. The exploit has been disclosed to the public and may be used. Upgrading to version 2.0.0 is able to address this issue. The name of the patch is caae2988ba2a37765d055c4eee63d383320ee662. It is recommended to upgrade the affected component. The associated identifier of this vulnerability is VDB-217451.
mime Regular Expression Denial of Service when MIME lookup performed on untrusted user input
Affected versions of mime are vulnerable to regular expression denial of service when a mime lookup is performed on untrusted user input.
Update to version 2.0.3 or later.
debug Inefficient Regular Expression Complexity vulnerability
A vulnerability classified as problematic has been found in debug-js debug up to 3.0.x. This affects the function useColors of the file src/node.js. The manipulation of the argument str leads to inefficient regular expression complexity. Upgrading to version 3.1.0 is able to address this issue. The name of the patch is c38a0166c266a679c8de012d4eaccec3f944e685. It is recommended to upgrade the affected component. The identifier VDB-217665 was assigned to this vulnerability. The patch has been backported to the 2.6.x branch in version 2.6.9.
Regular Expression Denial of Service in debug
Affected versions of debug are vulnerable to regular expression denial of service when untrusted user input is passed into the o formatter.
As it takes 50,000 characters to block the event loop for 2 seconds, this issue is a low severity issue.
This was later re-introduced in version v3.2.0, and then repatched in versions 3.2.7 and 4.3.1.
Version 2.x.x: Update to version 2.6.9 or later. Version 3.1.x: Update to version 3.1.0 or later. Version 3.2.x: Update to version 3.2.7 or later. Version 4.x.x: Update to version 4.3.1 or later.
Regular Expression Denial of Service in fresh
Affected versions of fresh are vulnerable to regular expression denial of service when parsing specially crafted user input.
Update to version 0.5.2 or later.
cookie accepts cookie name, path, and domain with out of bounds characters
The cookie name could be used to set other fields of the cookie, resulting in an unexpected cookie value. For example, serialize("userName=<script>alert('XSS3')</script>; Max-Age=2592000; a", value) would result in "userName=<script>alert('XSS3')</script>; Max-Age=2592000; a=test", setting userName cookie to <script> and ignoring value.
A similar escape can be used for path and domain, which could be abused to alter other fields of the cookie.
Upgrade to 0.7.0, which updates the validation for name, path, and domain.
Avoid passing untrusted or arbitrary values for these fields, ensure they are set by the application instead of user input.
Prototype Pollution in minimist
Affected versions of minimist are vulnerable to prototype pollution. Arguments are not properly sanitized, allowing an attacker to modify the prototype of Object, causing the addition or modification of an existing property that will exist on all objects.
Parsing the argument --__proto__.y=Polluted adds a y property with value Polluted to all objects. The argument --__proto__=Polluted raises and uncaught error and crashes the application.
This is exploitable if attackers have control over the arguments being passed to minimist.
Upgrade to versions 0.2.1, 1.2.3 or later.
Prototype Pollution in minimist
Minimist prior to 1.2.6 and 0.2.4 is vulnerable to Prototype Pollution via file index.js, function setKey() (lines 69-95).
basic-auth-connect's callback uses time unsafe string comparison
basic-auth-connect <1.1.0 uses a timing-unsafe equality comparison that can leak timing information
this issue has been fixed in basic-auth-connect 1.1.0
body-parser vulnerable to denial of service when url encoding is enabled
body-parser <1.20.3 is vulnerable to denial of service when url encoding is enabled. A malicious actor using a specially crafted payload could flood the server with a large number of requests, resulting in denial of service.
this issue is patched in 1.20.3
Regular Expression Denial of Service in negotiator
Affected versions of negotiator are vulnerable to regular expression denial of service attacks, which trigger upon parsing a specially crafted Accept-Language header value.
Update to version 0.6.1 or later.
Out-of-bounds Read in base64-url
Versions of base64-url before 2.0.0 are vulnerable to out-of-bounds read as it allocates uninitialized Buffers when number is passed in input.
Update to version 2.0.0 or later.
Code Injection in morgan
Verisons of morgan before 1.9.1 are vulnerable to code injection when user input is allowed into the filter or combined with a prototype pollution attack.
Update to version 1.9.1 or later.
on-headers is vulnerable to http response header manipulation
A bug in on-headers versions < 1.1.0 may result in response headers being inadvertently modified when an array is passed to response.writeHead()
Users should upgrade to 1.1.0
Uses are encouraged to upgrade to 1.1.0, but this issue can be worked around by passing an object to response.writeHead() rather than an array.
Prototype Pollution Protection Bypass in qs
Affected version of qs are vulnerable to Prototype Pollution because it is possible to bypass the protection. The qs.parse function fails to properly prevent an object's prototype to be altered when parsing arbitrary input. Input containing [ or ] may bypass the prototype pollution protection and alter the Object prototype. This allows attackers to override properties that will exist in all objects, which may lead to Denial of Service or Remote Code Execution in specific circumstances.
Upgrade to 6.0.4, 6.1.2, 6.2.3, 6.3.2 or later.
qs vulnerable to Prototype Pollution
qs before 6.10.3 allows attackers to cause a Node process hang because an __ proto__ key can be used. In many typical web framework use cases, an unauthenticated remote attacker can place the attack payload in the query string of the URL that is used to visit the application, such as a[__proto__]=b&a[__proto__]&a[length]=100000000. The fix was backported to qs 6.9.7, 6.8.3, 6.7.3, 6.6.1, 6.5.3, 6.4.1, 6.3.3, and 6.2.4.
Cross-Site Scripting in serve-index
Versions 1.6.2 and earlier of serve-index are affected by a cross-site scripting vulnerability. Because file and directory names are not escaped in the module's HTML output, a remote attacker that can influence file or directory names can launch a persistent cross-site scripting attack on the application.
Update to version 1.6.3 or later.
serve-static vulnerable to template injection that can lead to XSS
passing untrusted user input - even after sanitizing it - to redirect() may execute untrusted code
this issue is patched in serve-static 1.16.0
users are encouraged to upgrade to the patched version of express, but otherwise can workaround this issue by making sure any untrusted inputs are safe, ideally by validating them against an explicit allowlist
successful exploitation of this vector requires the following: