Astro
CVE-2026-27729
MEDIUM
Vulnerability Assessment
| Weakness |
CWE
OWASP Top 10:2025
A06:2025 - Insecure Design
ASVS 5.0
V2 - Validation and Business Logic Resource allocation limits
MITRE ATT&CK
1 technique across 1 tactic: Impact The technique list with ATT&CK links and the kill-chain view is part of the Basic plan and up. |
| Impact | CVSS 5.9 (MEDIUM). Attack vector: Network. Complexity: High. Privileges required: None. User interaction: None. Exploitation no authentication required. Public exploit/POC available. |
| Exploit ScenarioDerived | An attacker without authentication could exploit this vulnerability to memory exhaustion DoS. |
Get an e-mail when this CVE is exploited, patched or re-scored. Free account.
Alert meAnalysisAIv1 – Mar 12, 2026
Memory exhaustion denial of service in Astro 9.0.0 through 9.5.3 allows remote attackers to crash server processes by sending oversized POST requests to server action endpoints without size restrictions. The framework buffers entire request bodies into memory with no limits, enabling a single large request to exhaust heap memory on affected deployments. Public exploit code exists for this vulnerability, which is particularly impactful in containerized environments where repeated crashes trigger persistent restart loops.
Earlier versions of this analysis (1)
\@Astrojs\/Node versions up to 9.5.3 is affected by allocation of resources without limits or throttling (CVSS 5.9).
RemediationAI
A vendor patch is available — apply it immediately. Restrict network access to the affected service where possible.
Affected Packages
Source: OSV (Open Source Vulnerabilities)
Affects your stack
Affects 1 package in npm
Checking this CVE against your own stacks and servers is part of the Basic plan and up.
Technical ContextAI · show details
This vulnerability (CWE-770: Allocation of Resources Without Limits or Throttling) affects \@Astrojs\/Node. Astro is a web framework. In versions 9.0.0 through 9.5.3, Astro server actions have no default request body size limit, which can lead to memory exhaustion DoS. A single large POST to a valid action endpoint can crash the server process on memory-constrained deployments. On-demand rendered sites built with Astro can define server actions, which automatically parse incoming request bodies (JSON or FormData). The body is buffered entirely into memory with no size limit — a single oversized reques
Know when Astro gets its next vulnerability
- Watch products and get an email when something new is published
- Check this CVE against your own stack and servers
- Exploit and PoC references, threat intelligence from 22 sources
No credit card · 7-day full trial
Severity by source
AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
Primary rating from GitHub Advisory · only source for this CVE.
CVSS VectorGitHub Advisory
Lifecycle Timeline
3DescriptionGitHub Advisory
Astro is a web framework. In versions 9.0.0 through 9.5.3, Astro server actions have no default request body size limit, which can lead to memory exhaustion DoS. A single large POST to a valid action endpoint can crash the server process on memory-constrained deployments. On-demand rendered sites built with Astro can define server actions, which automatically parse incoming request bodies (JSON or FormData). The body is buffered entirely into memory with no size limit - a single oversized request is sufficient to exhaust the process heap and crash the server. Astro's Node adapter (mode: 'standalone') creates an HTTP server with no body size protection. In containerized environments, the crashed process is automatically restarted, and repeated requests cause a persistent crash-restart loop. Action names are discoverable from HTML form attributes on any public page, so no authentication is required. The vulnerability allows unauthenticated denial of service against SSR standalone deployments using server actions. A single oversized request crashes the server process, and repeated requests cause a persistent crash-restart loop in containerized environments. Version 9.5.4 contains a fix.
Executive ViewAI
Organizations using versions 9.0.0 should be aware of moderate risk from CVE-2026-27729 rated CVSS 5.9. Exploitation could compromise the security of affected deployments. Proof-of-concept code is publicly available. A patch is available and should be applied during regular vulnerability management.
Apply vendor patch. If patching is delayed: restrict network access and enable monitoring.
Threat Intelligence Overview
How this decision was reached
The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.
What every action level means
SSVC AssessmentENISA
Priority Score
Attack Technique
Denial of Service attacks render applications or systems unavailable by overwhelming resources or triggering failure conditions.
Affected Products (CPE)GitHub Advisory
SQL Injection exists in the Saxum Astro 4.0.14 component for Joomla!. Rated critical severity (CVSS 9.8), this vulnerabi
Astro web framework versions prior to 9.5.4 contain a server-side request forgery vulnerability in error page handling t
Authorization bypass in the Astro web framework version 6.4.7 lets remote unauthenticated attackers reach protected rout
Astro is a web framework for content-driven websites. Rated high severity (CVSS 7.8), this vulnerability is remotely exp
Server-side request forgery in Astro's built-in image proxy lets unauthenticated remote attackers force the server to fe
Astro is a web framework for content-driven websites. Rated high severity (CVSS 7.2), this vulnerability is remotely exp
Astro is a web framework for content-driven websites. Rated medium severity (CVSS 6.9), this vulnerability is remotely e
Astro is a web framework. Rated medium severity (CVSS 6.9), this vulnerability is remotely exploitable, no authenticatio
Astro is a web framework. Rated medium severity (CVSS 6.5), this vulnerability is remotely exploitable, no authenticatio
Unvalidated reflection of the X-Forwarded-Host header in Astro (versions before 5.14.3) lets remote, unauthenticated att
Astro web framework versions 9.0.0 through 9.5.3 fail to validate remote image domains when the inferSize option is enab
Base-path prefix bypass in Astro prior to 7.2.4 allows unauthenticated remote attackers to reach protected server-side r
GHSA-jm64-8m5q-4qh8
NVD
CVE.org
EPSS
Exploit-DB