chore(deps): update dependency postcss to v8.5.10 [security]

[renovate]

RicardoGEsteves all-non-major update, dependency postcss to v8.5.10

This PR contains the following updates:

Package	Type	Update	Change	OpenSSF	New value	Package file	References
postcss (source)	devDependencies	patch	8.5.3 → 8.5.10		8.5.10	package.json	homepage, source

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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).

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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).

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Configuration

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⚠️ Artifact update problem

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The artifact failure details are included below:

File name: package-lock.json

npm warn Unknown env config "store". This will stop working in the next major version of npm. See `npm help npmrc` for supported config options.
npm error code ERESOLVE
npm error ERESOLVE unable to resolve dependency tree
npm error
npm error While resolving: digital-marketplace@0.1.0
npm error Found: payload@2.32.0
npm error node_modules/payload
npm error   payload@"2.32.0" from the root project
npm error
npm error Could not resolve dependency:
npm error peer payload@"3.25.0" from @payloadcms/db-mongodb@3.25.0
npm error node_modules/@payloadcms/db-mongodb
npm error   @payloadcms/db-mongodb@"3.25.0" from the root project
npm error
npm error Fix the upstream dependency conflict, or retry this command with --force or --legacy-peer-deps to accept an incorrect (and potentially broken) dependency resolution.
npm error
npm error
npm error For a full report see:
npm error /runner/cache/others/npm/_logs/2026-08-12T01_45_04_564Z-eresolve-report.txt
npm error A complete log of this run can be found in: /runner/cache/others/npm/_logs/2026-08-12T01_45_04_564Z-debug-0.log