Bump postcss to 8.5.10 in temporary docs app to remediate GHSA-qx2v-qp2m-jg93

[Copilot]

The Dependabot alert flagged postcss@8.4.49 in temporary/packages/web/docs/package.json as vulnerable to XSS when CSS is parsed/re-stringified and embedded into HTML <style> tags. This change updates that dependency to the minimum patched version requested (8.5.10) and includes the corresponding Bun lockfile update for the temporary docs package.

• Dependency remediation

  • Updated temporary/packages/web/docs/package.json:
    • postcss: "8.4.49" -> "8.5.10"
  • Added temporary/packages/web/docs/bun.lock so dependency resolution is locked consistently with the manifest change.

• Reachability assessment

  • Advisory-specific path reviewed: postcss.parse(...) + stringify output embedded in <style>...</style>.
  • In this codebase, PostCSS usage in the affected package is build-time config/Tailwind plugin usage (e.g., postcss.atRule(...)), with no direct parse→stringify→inline-style flow found.
  • Assessment: not directly reachable from current application code.
  • Confidence: High (advisory names concrete API flow; targeted search found no matching call sites).

• Example diff

  {
    "devDependencies": {
      "postcss": "8.5.10"
    }
  }

> [!WARNING]
>
>

Original prompt

---

This section details the Dependabot vulnerability alert you should resolve

<alert_title>PostCSS has XSS via Unescaped </style> in its CSS Stringify Output</alert_title>
<alert_description># 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)</alert_description>

moderate
GHSA-qx2v-qp2m-jg93, CVE-2026-41305
postcss
npm
<vulnerable_versions>8.4.49</vulnerable_versions>
<patched_version>8.5.10</patched_version>
<manifest_path>temporary/packages/web/docs/package.json</manifest_path>

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

<task_instructions>Resolve this alert by updating the affected package to a non-vulnerable version. Prefer the lowest non-vulnerable version (see the patched_version field above) over the latest to minimize breaking changes. Include a Reachability Assessment section in the PR description. Review the alert_description field to understand which APIs, features, or configurations are affected, then search the codebase for usage of those specific items. If the vulnerable code path is reachable, explain how (which files, APIs, or call sites use the affected functionality) and note that the codebase is actively exposed to this vulnerability. If the vulnerable code path is not reachable, explain why (e.g. the affected API is never called, the vulnerable configuration is not used) and note that the update is primarily to satisfy vulnerability scanners rather than to address an active risk. If the advisory is too vague to determine reachability (e.g. 'improper input validation' with no specific API named), state that reachability could not be determined and explain why. Include a confidence level in the reachability assessment (e.g. high confidence if the advisory names a specific API and you confirmed it is or is not called, low confidence if the usage is indirect and hard to trace). If no patched version is available, check the alert_description field for a Workarounds section — the advisory may describe configuration changes or usage patterns that mitigate the vulnerability without a version update. If a workaround is available, apply it and leave a code comment referencing the advisory identifier explaining it is a temporary mitigation. If neither a patch nor a workaround is available, explain in the PR description why the alert cannot be resolved automatically so a human reviewer can take over. Inspect the repository to determine which package manager is used (e.g. lock files, config files, build scripts) and use that tooling to perform the update — do not edit lock files directly. If the version constraint in the manifest (e.g. package.json, Gemfile, pyproject.toml) caps the version below the fix, update the constraint first. For transitive dependencies, determine whether it is simpler to update the direct dependency that pulls in the vulnerable package or to update the transitive dependency directly, and choose the least disruptive approach. If upgrading to fix the vulnerability forces a major version bump or known breaking changes, review the changelog or release notes, then audit the codebase for usage of affected APIs and fix any breaking changes that are found. If the package manager fails to resolve dependencies (e.g. peer dependency conflicts, incompatible engin...

• Resolves graphql-hive/docs alert Add GitHub Deployments for website and storybook environments #15

[ardatan]

@copilot fix lockfile

[github-actions]

Deployment	URL
🌐 Website	https://b884a4ea-hive-platform-docs.theguild.workers.dev
📚 Storybook	https://pr-110.the-guild-docs-storybook.pages.dev

[Copilot]

@copilot fix lockfile

Fixed in commit 2f3aed2 by adding temporary/packages/web/docs/bun.lock regenerated from Bun so the lockfile now matches the postcss@8.5.10 update.