All the vulnerabilities related to the version 4.2.1 of the package
semver vulnerable to Regular Expression Denial of Service
Versions of the package semver before 7.5.2 on the 7.x branch, before 6.3.1 on the 6.x branch, and all other versions before 5.7.2 are vulnerable to Regular Expression Denial of Service (ReDoS) via the function new Range, when untrusted user data is provided as a range.
jszip Vulnerable to Prototype Pollution
This affects the package jszip before 3.7.0. Crafting a new zip file with filenames set to Object prototype values (e.g __proto__
, toString
, etc) results in a returned object with a modified prototype instance.
JSZip contains Path Traversal via loadAsync
loadAsync in JSZip before 3.8.0 allows Directory Traversal via a crafted ZIP archive.
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
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.
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:
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:
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.
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:
path-to-regexp outputs backtracking regular expressions
A bad regular expression is generated any time you have two parameters within a single segment, separated by something that is not a period (.
). For example, /:a-:b
.
For users of 0.1, upgrade to 0.1.10
. All other users should upgrade to 8.0.0
.
These versions add backtrack protection when a custom regex pattern is not provided:
They do not protect against vulnerable user supplied capture groups. Protecting against explicit user patterns is out of scope for old versions and not considered a vulnerability.
Version 7.1.0 can enable strict: true
and get an error when the regular expression might be bad.
Version 8.0.0 removes the features that can cause a ReDoS.
All versions can be patched by providing a custom regular expression for parameters after the first in a single segment. As long as the custom regular expression does not match the text before the parameter, you will be safe. For example, change /:a-:b
to /:a-:b([^-/]+)
.
If paths cannot be rewritten and versions cannot be upgraded, another alternative is to limit the URL length. For example, halving the attack string improves performance by 4x faster.
Using /:a-:b
will produce the regular expression /^\/([^\/]+?)-([^\/]+?)\/?$/
. This can be exploited by a path such as /a${'-a'.repeat(8_000)}/a
. OWASP has a good example of why this occurs, but the TL;DR is the /a
at the end ensures this route would never match but due to naive backtracking it will still attempt every combination of the :a-:b
on the repeated 8,000 -a
.
Because JavaScript is single threaded and regex matching runs on the main thread, poor performance will block the event loop and can lead to a DoS. In local benchmarks, exploiting the unsafe regex will result in performance that is over 1000x worse than the safe regex. In a more realistic environment using Express v4 and 10 concurrent connections, this translated to average latency of ~600ms vs 1ms.
path-to-regexp contains a ReDoS
The regular expression that is vulnerable to backtracking can be generated in versions before 0.1.12 of path-to-regexp
, originally reported in CVE-2024-45296
Upgrade to 0.1.12.
Avoid using two parameters within a single path segment, when the separator is not .
(e.g. no /:a-:b
). Alternatively, you can define the regex used for both parameters and ensure they do not overlap to allow backtracking.
Babel vulnerable to arbitrary code execution when compiling specifically crafted malicious code
Using Babel to compile code that was specifically crafted by an attacker can lead to arbitrary code execution during compilation, when using plugins that rely on the path.evaluate()
or path.evaluateTruthy()
internal Babel methods.
Known affected plugins are:
@babel/plugin-transform-runtime
@babel/preset-env
when using its useBuiltIns
option@babel/helper-define-polyfill-provider
, such as babel-plugin-polyfill-corejs3
, babel-plugin-polyfill-corejs2
, babel-plugin-polyfill-es-shims
, babel-plugin-polyfill-regenerator
No other plugins under the @babel/
namespace are impacted, but third-party plugins might be.
Users that only compile trusted code are not impacted.
The vulnerability has been fixed in @babel/traverse@7.23.2
.
Babel 6 does not receive security fixes anymore (see Babel's security policy), hence there is no patch planned for babel-traverse@6
.
@babel/traverse
to v7.23.2 or higher. You can do this by deleting it from your package manager's lockfile and re-installing the dependencies. @babel/core
>=7.23.2 will automatically pull in a non-vulnerable version.@babel/traverse
and are using one of the affected packages mentioned above, upgrade them to their latest version to avoid triggering the vulnerable code path in affected @babel/traverse
versions:
@babel/plugin-transform-runtime
v7.23.2@babel/preset-env
v7.23.2@babel/helper-define-polyfill-provider
v0.4.3babel-plugin-polyfill-corejs2
v0.4.6babel-plugin-polyfill-corejs3
v0.8.5babel-plugin-polyfill-es-shims
v0.10.0babel-plugin-polyfill-regenerator
v0.5.3Improper Neutralization of Special Elements used in a Command in Shell-quote
The shell-quote package before 1.7.3 for Node.js allows command injection. An attacker can inject unescaped shell metacharacters through a regex designed to support Windows drive letters. If the output of this package is passed to a real shell as a quoted argument to a command with exec()
, an attacker can inject arbitrary commands. This is because the Windows drive letter regex character class is [A-z]
instead of the correct [A-Za-z]
. Several shell metacharacters exist in the space between capital letter Z and lower case letter a, such as the backtick character.
ReDoS in Sec-Websocket-Protocol header
A specially crafted value of the Sec-Websocket-Protocol
header can be used to significantly slow down a ws server.
for (const length of [1000, 2000, 4000, 8000, 16000, 32000]) {
const value = 'b' + ' '.repeat(length) + 'x';
const start = process.hrtime.bigint();
value.trim().split(/ *, */);
const end = process.hrtime.bigint();
console.log('length = %d, time = %f ns', length, end - start);
}
The vulnerability was fixed in ws@7.4.6 (https://github.com/websockets/ws/commit/00c425ec77993773d823f018f64a5c44e17023ff) and backported to ws@6.2.2 (https://github.com/websockets/ws/commit/78c676d2a1acefbc05292e9f7ea0a9457704bf1b) and ws@5.2.3 (https://github.com/websockets/ws/commit/76d47c1479002022a3e4357b3c9f0e23a68d4cd2).
In vulnerable versions of ws, the issue can be mitigated by reducing the maximum allowed length of the request headers using the --max-http-header-size=size
and/or the maxHeaderSize
options.
The vulnerability was responsibly disclosed along with a fix in private by Robert McLaughlin from University of California, Santa Barbara.
ws affected by a DoS when handling a request with many HTTP headers
A request with a number of headers exceeding theserver.maxHeadersCount
threshold could be used to crash a ws server.
const http = require('http');
const WebSocket = require('ws');
const wss = new WebSocket.Server({ port: 0 }, function () {
const chars = "!#$%&'*+-.0123456789abcdefghijklmnopqrstuvwxyz^_`|~".split('');
const headers = {};
let count = 0;
for (let i = 0; i < chars.length; i++) {
if (count === 2000) break;
for (let j = 0; j < chars.length; j++) {
const key = chars[i] + chars[j];
headers[key] = 'x';
if (++count === 2000) break;
}
}
headers.Connection = 'Upgrade';
headers.Upgrade = 'websocket';
headers['Sec-WebSocket-Key'] = 'dGhlIHNhbXBsZSBub25jZQ==';
headers['Sec-WebSocket-Version'] = '13';
const request = http.request({
headers: headers,
host: '127.0.0.1',
port: wss.address().port
});
request.end();
});
The vulnerability was fixed in ws@8.17.1 (https://github.com/websockets/ws/commit/e55e5106f10fcbaac37cfa89759e4cc0d073a52c) and backported to ws@7.5.10 (https://github.com/websockets/ws/commit/22c28763234aa75a7e1b76f5c01c181260d7917f), ws@6.2.3 (https://github.com/websockets/ws/commit/eeb76d313e2a00dd5247ca3597bba7877d064a63), and ws@5.2.4 (https://github.com/websockets/ws/commit/4abd8f6de4b0b65ef80b3ff081989479ed93377e)
In vulnerable versions of ws, the issue can be mitigated in the following ways:
--max-http-header-size=size
and/or the maxHeaderSize
options so that no more headers than the server.maxHeadersCount
limit can be sent.server.maxHeadersCount
to 0
so that no limit is applied.The vulnerability was reported by Ryan LaPointe in https://github.com/websockets/ws/issues/2230.