CVE-2026-27729 - Vulnerability Analysis

Overview

Astro 9.0.0 through 9.5.3 contains a denial of service caused by lack of request body size limit in server actions, letting unauthenticated attackers crash the server via oversized POST requests, exploit requires no authentication.

Severity & Score

Impact

Unauthenticated attackers can crash the server process causing denial of service and persistent crash-restart loops in containerized environments.

Mitigation

Upgrade to version 9.5.4 or later.

References

• https://github.com/withastro/astro/commit/522f880b07a4ea7d69a19b5507fb53a5ed6c87f8
• https://github.com/withastro/astro/pull/15564
• https://github.com/withastro/astro/releases/tag/%40astrojs%2Fnode%409.5.4
• https://github.com/withastro/astro/security/advisories/GHSA-jm64-8m5q-4qh8

Related Resources

• Vulnerability Intelligence Dashboard
• Credential Scanner