# Astro astro@5.15.8 — Release & Upgrade Intelligence
- **Product:** Astro (https://astro.build)
- **Version:** astro@5.15.8
- **Released:** Nov 15, 2025
- **Impact Score:** 5/10
- **Breaking Changes:** Not verified
- **Canonical Analysis:** https://changelogs.us/astro/updates/astro-5.15.8/

## Executive Summary (TL;DR)
Astro astro@5.15.8. Source highlight: Improves the security of Server Islands slots by encrypting them before transmission to the browser, matching the security model used for props. This improves the integrity of slot content and prevents injection attacks, even when component templates don't explicitly support slots.

## Bug Fixes
- Improves the security of Server Islands slots by encrypting them before transmission to the browser, matching the security model used for props. This improves the integrity of slot content and prevents injection attacks, even when component templates don't explicitly support slots.
- Fix middleware pathname matching by normalizing URL-encoded paths

## Upgrade Command
```bash
npm install --save-exact astro@5.15.8
```