5.1
MEDIUM CVSS 4.0
CVE-2026-73423
Astro: composable `astro/hono` pipeline bypasses `security.checkOrigin` when `middleware()` is absent or misordered
Description

Astro is a web framework for content-driven websites. From 7.0.0 until 7.0.6, the composable astro/hono pipeline installs security.checkOrigin only through the middleware() primitive, while actions() and pages() can dispatch to user code independently. Mounting actions() before middleware(), as in the examples/advanced-routing example and Cloudflare Hono documentation, allows cross-origin form-encoded action requests to execute before the origin check, and using pages() without middleware() drops the check for on-demand endpoints and pages. The flaw enables blind write-only cross-site request forgery using the victim's cookies against ActionHandler.handle and PagesHandler.handleWithErrorFallback when manifest.checkOrigin is enabled; the attacker can trigger a state-mutating action or endpoint handler but cannot read the cross-origin response. The default non-composable astro() pipeline is not affected. This issue is fixed in version 7.0.6.

INFO

Published Date :

Aug. 12, 2026, 9:17 p.m.

Last Modified :

Aug. 12, 2026, 9:17 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-73423 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 4.0 MEDIUM [email protected]
Solution
Update Astro to version 7.0.6 or later to fix the cross-origin request forgery vulnerability.
  • Update Astro to version 7.0.6 or later.
  • Ensure security.checkOrigin is used correctly in middleware.
  • Verify ActionHandler and PagesHandler are protected.
  • Review advanced-routing examples for security.
References to Advisories, Solutions, and Tools
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-73423 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-73423 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-73423 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-73423 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by [email protected]

    Aug. 12, 2026

    Action Type Old Value New Value
    Added Affected [{'vendor': 'withastro', 'product': 'astro', 'versions': [{'status': 'affected', 'version': '>= 7.0.0, < 7.0.6'}]}]
    Added Description Astro is a web framework for content-driven websites. From 7.0.0 until 7.0.6, the composable astro/hono pipeline installs security.checkOrigin only through the middleware() primitive, while actions() and pages() can dispatch to user code independently. Mounting actions() before middleware(), as in the examples/advanced-routing example and Cloudflare Hono documentation, allows cross-origin form-encoded action requests to execute before the origin check, and using pages() without middleware() drops the check for on-demand endpoints and pages. The flaw enables blind write-only cross-site request forgery using the victim's cookies against ActionHandler.handle and PagesHandler.handleWithErrorFallback when manifest.checkOrigin is enabled; the attacker can trigger a state-mutating action or endpoint handler but cannot read the cross-origin response. The default non-composable astro() pipeline is not affected. This issue is fixed in version 7.0.6.
    Added CVSS V4.0 AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:N/SC:N/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
    Added CWE CWE-352
    Added Reference https://github.com/withastro/astro/commit/0b30b35f864310bee8485c952d1877e82e2b9b1a
    Added Reference https://github.com/withastro/astro/pull/17250
    Added Reference https://github.com/withastro/astro/releases/tag/[email protected]
    Added Reference https://github.com/withastro/astro/security/advisories/GHSA-8mv7-9c27-98vc
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.