All the vulnerabilities related to the version 0.0.8 of the package
No Charset in Content-Type Header in express
Vulnerable versions of express do not specify a charset field in the content-type header while displaying 400 level response messages. The lack of enforcing user's browser to set correct charset, could be leveraged by an attacker to perform a cross-site scripting attack, using non-standard encodings, like UTF-7.
For express 3.x, update express to version 3.11 or later. For express 4.x, update express to version 4.5 or later.
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:
Directory Traversal in send
Versions 0.8.3 and earlier of send
are affected by a directory traversal vulnerability. When relying on the root option to restrict file access it may be possible for an application consumer to escape out of the restricted directory and access files in a similarly named directory.
For example, static(_dirname + '/public')
would allow access to _dirname + '/public-restricted'
.
Update to version 0.8.4 or later.
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:
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.
Cross-Site Scripting in connect
connect node module before 2.14.0 suffers from a Cross-Site Scripting (XSS) vulnerability due to a lack of validation of file in directory.js middleware.
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.
cookie-signature Timing Attack
Affected versions of cookie-signature
are vulnerable to timing attacks as a result of using a fail-early comparison instead of a constant-time comparison.
Timing attacks remove the exponential increase in entropy gained from increased secret length, by providing per-character feedback on the correctness of a guess via miniscule timing differences.
Under favorable network conditions, an attacker can exploit this to guess the secret in no more than charset*length
guesses, instead of charset^length
guesses required were the timing attack not present.
Update to 1.0.4 or later.
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.
Server-Side Request Forgery in Request
The request
package through 2.88.2 for Node.js and the @cypress/request
package prior to 3.0.0 allow a bypass of SSRF mitigations via an attacker-controller server that does a cross-protocol redirect (HTTP to HTTPS, or HTTPS to HTTP).
NOTE: The request
package is no longer supported by the maintainer.
form-data uses unsafe random function in form-data for choosing boundary
form-data uses Math.random()
to select a boundary value for multipart form-encoded data. This can lead to a security issue if an attacker:
Because the values of Math.random() are pseudo-random and predictable (see: https://blog.securityevaluators.com/hacking-the-javascript-lottery-80cc437e3b7f), an attacker who can observe a few sequential values can determine the state of the PRNG and predict future values, includes those used to generate form-data's boundary value. The allows the attacker to craft a value that contains a boundary value, allowing them to inject additional parameters into the request.
This is largely the same vulnerability as was recently found in undici
by parrot409
-- I'm not affiliated with that researcher but want to give credit where credit is due! My PoC is largely based on their work.
The culprit is this line here: https://github.com/form-data/form-data/blob/426ba9ac440f95d1998dac9a5cd8d738043b048f/lib/form_data.js#L347
An attacker who is able to predict the output of Math.random() can predict this boundary value, and craft a payload that contains the boundary value, followed by another, fully attacker-controlled field. This is roughly equivalent to any sort of improper escaping vulnerability, with the caveat that the attacker must find a way to observe other Math.random() values generated by the application to solve for the state of the PRNG. However, Math.random() is used in all sorts of places that might be visible to an attacker (including by form-data itself, if the attacker can arrange for the vulnerable application to make a request to an attacker-controlled server using form-data, such as a user-controlled webhook -- the attacker could observe the boundary values from those requests to observe the Math.random() outputs). A common example would be a x-request-id
header added by the server. These sorts of headers are often used for distributed tracing, to correlate errors across the frontend and backend. Math.random()
is a fine place to get these sorts of IDs (in fact, opentelemetry uses Math.random for this purpose)
PoC here: https://github.com/benweissmann/CVE-2025-7783-poc
Instructions are in that repo. It's based on the PoC from https://hackerone.com/reports/2913312 but simplified somewhat; the vulnerable application has a more direct side-channel from which to observe Math.random() values (a separate endpoint that happens to include a randomly-generated request ID).
For an application to be vulnerable, it must:
form-data
to send data including user-controlled data to some other system. The attacker must be able to do something malicious by adding extra parameters (that were not intended to be user-controlled) to this request. Depending on the target system's handling of repeated parameters, the attacker might be able to overwrite values in addition to appending values (some multipart form handlers deal with repeats by overwriting values instead of representing them as an array)If an application is vulnerable, this allows an attacker to make arbitrary requests to internal systems.
tough-cookie Prototype Pollution vulnerability
Versions of the package tough-cookie before 4.1.3 are vulnerable to Prototype Pollution due to improper handling of Cookies when using CookieJar in rejectPublicSuffixes=false
mode. This issue arises from the manner in which the objects are initialized.
Regular Expression Denial of Service in clean-css
Version of clean-css
prior to 4.1.11 are vulnerable to Regular Expression Denial of Service (ReDoS). Untrusted input may cause catastrophic backtracking while matching regular expressions. This can cause the application to be unresponsive leading to Denial of Service.
Upgrade to version 4.1.11 or higher.