Update dependency postcss to v8.5.10 [SECURITY]

[renovate]

This PR contains the following updates:

Package	Change	Age	Adoption	Passing	Confidence
postcss (source)	8.4.31 → 8.5.10

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PostCSS line return parsing error

CVE-2023-44270 / GHSA-7fh5-64p2-3v2j

More information

Details

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.

Severity

• CVSS Score: 5.3 / 10 (Medium)
• Vector String: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

References

• https://nvd.nist.gov/vuln/detail/CVE-2023-44270
• https://github.com/postcss/postcss/commit/58cc860b4c1707510c9cd1bc1fa30b423a9ad6c5
• https://github.com/postcss/postcss/blob/main/lib/tokenize.js#L25
• https://github.com/postcss/postcss/releases/tag/8.4.31
• https://github.com/github/advisory-database/issues/2820
• https://lists.debian.org/debian-lts-announce/2024/12/msg00025.html
• https://github.com/advisories/GHSA-7fh5-64p2-3v2j

This data is provided by the GitHub Advisory Database (CC-BY 4.0).

---

PostCSS has XSS via Unescaped </style> in its CSS Stringify Output

CVE-2026-41305 / GHSA-qx2v-qp2m-jg93

More information

Details

PostCSS: XSS via Unescaped </style> in CSS Stringify Output

Summary

PostCSS v8.5.5 (latest) does not escape </style> sequences when stringifying CSS ASTs. When user-submitted CSS is parsed and re-stringified for embedding in HTML <style> tags, </style> in CSS values breaks out of the style context, enabling XSS.

Proof of Concept

const postcss = require('postcss');

// Parse user CSS and re-stringify for page embedding
const userCSS = 'body { content: "</style><script>alert(1)</script><style>"; }';
const ast = postcss.parse(userCSS);
const output = ast.toResult().css;
const html = `<style>${output}</style>`;

console.log(html);
// <style>body { content: "</style><script>alert(1)</script><style>"; }</style>
//
// Browser: </style> closes the style tag, <script> executes

Tested output (Node.js v22, postcss v8.5.5):

Input: body { content: "</style><script>alert(1)</script><style>"; }
Output: body { content: "</style><script>alert(1)</script><style>"; }
Contains </style>: true

Impact

Impact non-bundler use cases since bundlers for XSS on their own. Requires some PostCSS plugin to have malware code, which can inject XSS to website.

Suggested Fix

Escape </style in all stringified output values:

output = output.replace(/<\/(style)/gi, '<\\/$1');

Credits

Discovered and reported by Sunil Kumar (@​TharVid)

Severity

• CVSS Score: 6.1 / 10 (Medium)
• Vector String: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

References

• https://github.com/postcss/postcss/security/advisories/GHSA-qx2v-qp2m-jg93
• https://nvd.nist.gov/vuln/detail/CVE-2026-41305
• https://github.com/postcss/postcss/releases/tag/8.5.10
• https://github.com/advisories/GHSA-qx2v-qp2m-jg93

This data is provided by the GitHub Advisory Database (CC-BY 4.0).

---

Release Notes

postcss/postcss (postcss)

v8.5.10

Compare Source

• Fixed XSS via unescaped </style> in non-bundler cases (by @​TharVid).

v8.5.9

Compare Source

• Speed up source map encoding paring in case of the error.

v8.5.8

Compare Source

• Fixed Processor#version.

v8.5.7

Compare Source

• Improved source map annotation cleaning performance (by CodeAnt AI).

v8.5.6

Compare Source

• Fixed ContainerWithChildren type discriminating (by @​Goodwine).

v8.5.5

Compare Source

• Fixed package.json→exports compatibility with some tools (by @​JounQin).

v8.5.4

Compare Source

• Fixed Parcel compatibility issue (by @​git-sumitchaudhary).

v8.5.3

Compare Source

• Added more details to Unknown word error (by @​hiepxanh).
• Fixed types (by @​romainmenke).
• Fixed docs (by @​catnipan).

v8.5.2

Compare Source

• Fixed end position of rules with semicolon (by @​romainmenke).

v8.5.1

Compare Source

• Fixed backwards compatibility for complex cases (by @​romainmenke).

v8.5.0: 8.5 “Duke Alloces”

Compare Source

PostCSS 8.5 brought API to work better with non-CSS sources like HTML, Vue.js/Svelte sources or CSS-in-JS.

@​romainmenke during his work on Stylelint added Input#document in additional to Input#css.

root.source.input.document //=> "<p>Hello</p>
                           //    <style>
                           //    p {
                           //      color: green;
                           //    }
                           //    </style>"
root.source.input.css      //=> "p {
                           //      color: green;
                           //    }"

Thanks to Sponsors

This release was possible thanks to our community.

If your company wants to support the sustainability of front-end infrastructure or wants to give some love to PostCSS, you can join our supporters by:

• Tidelift with a Spotify-like subscription model supporting all projects from your lock file.
• Direct donations at GitHub Sponsors or Open Collective.

v8.4.49

Compare Source

• Fixed custom syntax without source.offset (by @​romainmenke).

v8.4.48

Compare Source

• Fixed position calculation in error/warnings methods (by @​romainmenke).

v8.4.47

Compare Source

• Removed debug code.

v8.4.46

Compare Source

• Fixed Cannot read properties of undefined (reading 'before').

v8.4.45

Compare Source

• Removed unnecessary fix which could lead to infinite loop.

v8.4.44

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• Another way to fix markClean is not a function error.

v8.4.43

Compare Source

• Fixed markClean is not a function error.

v8.4.42

Compare Source

• Fixed CSS syntax error on long minified files (by @​varpstar).

v8.4.41

Compare Source

• Fixed types (by @​nex3 and @​querkmachine).
• Cleaned up RegExps (by @​bluwy).

v8.4.40

Compare Source

• Moved to getter/setter in nodes types to help Sass team (by @​nex3).

v8.4.39

Compare Source

• Fixed CssSyntaxError types (by @​romainmenke).

v8.4.38

Compare Source

• Fixed endIndex: 0 in errors and warnings (by @​romainmenke).

v8.4.37

Compare Source

• Fixed original.column are not numbers error in another case.

v8.4.36

Compare Source

• Fixed original.column are not numbers error on broken previous source map.

v8.4.35

Compare Source

• Avoid ! in node.parent.nodes type.
• Allow to pass undefined to node adding method to simplify types.

v8.4.34

Compare Source

• Fixed AtRule#nodes type (by Tim Weißenfels).
• Cleaned up code (by Dmitry Kirillov).

v8.4.33

Compare Source

• Fixed NoWorkResult behavior difference with normal mode (by Romain Menke).
• Fixed NoWorkResult usage conditions (by @​ahmdammarr).

v8.4.32

Compare Source

• Fixed postcss().process() types (by Andrew Ferreira).

---

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[cr-gpt]

Seems you are using me but didn't get OPENAI_API_KEY seted in Variables/Secrets for this repo. you could follow readme for more information

[socket-security]

Warning

Review the following alerts detected in dependencies.

According to your organization's Security Policy, it is recommended to resolve "Warn" alerts. Learn more about Socket for GitHub.

Action	Severity	Alert  (click "▶" to expand/collapse)
Warn		Obfuscated code: npm svelte is 91.0% likely obfuscated Confidence: 0.91 Location: Package overview From: pnpm-lock.yaml → npm/novel@0.1.22 → npm/ai@2.1.17 → npm/svelte@4.2.20 ℹ Read more on: This package | This alert | What is obfuscated code? Next steps: Take a moment to review the security alert above. Review the linked package source code to understand the potential risk. Ensure the package is not malicious before proceeding. If you're unsure how to proceed, reach out to your security team or ask the Socket team for help at support@socket.dev. Suggestion: Packages should not obfuscate their code. Consider not using packages with obfuscated code. Mark the package as acceptable risk. To ignore this alert only in this pull request, reply with the comment @SocketSecurity ignore npm/svelte@4.2.20. You can also ignore all packages with @SocketSecurity ignore-all. To ignore an alert for all future pull requests, use Socket's Dashboard to change the triage state of this alert.

View full report

[cr-gpt]

Seems you are using me but didn't get OPENAI_API_KEY seted in Variables/Secrets for this repo. you could follow readme for more information

[cr-gpt]

Seems you are using me but didn't get OPENAI_API_KEY seted in Variables/Secrets for this repo. you could follow readme for more information

[cr-gpt]

Seems you are using me but didn't get OPENAI_API_KEY seted in Variables/Secrets for this repo. you could follow readme for more information

[socket-security]

Review the following changes in direct dependencies. Learn more about Socket for GitHub.

Diff	Package	Supply Chain Security	Vulnerability	Quality	Maintenance	License
	postcss@​8.5.10

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