# Astro astro@5.18.0 — Release & Upgrade Intelligence
- **Product:** Astro (https://astro.build)
- **Version:** astro@5.18.0
- **Released:** Feb 25, 2026
- **Impact Score:** 5/10
- **Breaking Changes:** Not verified
- **Canonical Analysis:** https://changelogs.us/astro/updates/astro-5.18.0/

## Executive Summary (TL;DR)
Astro astro@5.18.0. Source highlight: Adds a new `security.actionBodySizeLimit` option to configure the maximum size of Astro Actions request bodies.

## New Features
- Adds a new `security.actionBodySizeLimit` option to configure the maximum size of Astro Actions request bodies.

## Bug Fixes
- Fix X-Forwarded-Proto validation when allowedDomains includes both protocol and hostname fields. The protocol check no longer fails due to hostname mismatch against the hardcoded test URL.

## Upgrade Command
```bash
npm install --save-exact astro@5.18.0
```