Astro development server error page is vulnerable to reflected Cross-site Scripting

Description

A Reflected Cross-Site Scripting (XSS) vulnerability exists in Astro’s development server error pages when the trailingSlash configuration option is used. An attacker can inject arbitrary JavaScript code that executes in the victim’s browser context by crafting a malicious URL.

Recommendation

Update the astro package to the latest compatible version. Followings are version details:

• Affected version(s): >= 5.2.0, < 5.15.6
• Patched version(s): 5.15.6

References

• GHSA-w2vj-39qv-7vh7
• CVE-2025-64745
• CWE-79
• CAPEC-310
• OWASP 2021-A3
• OWASP 2021-A6

Related Issues

• `vega-functions` vulnerable to Cross-site Scripting via `setdata` function - CVE-2025-66648
• Astro Cloudflare adapter has Stored Cross-site Scripting vulnerability in /_image endpoint - CVE-2025-65019
• Parse Server has a Cross-Site Scripting (XSS) vulnerability via Unescaped Mustache Template Variables - CVE-2025-68115
• Vega vulnerable to Cross-site Scripting via RegExp.prototype[@@replace] - vega - CVE-2025-27793

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Tags:

npm

astro