Astro is a web framework. Starting in version 5.2.0 and prior to version 5.15.6, 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. While this vulnerability only affects the development server and not production builds, it could be exploited to compromise developer environments through social engineering or malicious links. Version 5.15.6 fixes the issue.
CVSS Score
2.7
EPSS Score
0.002
Published
2025-11-13
Astro is a web framework. In Astro versions 2.16.0 up to but excluding 5.15.5 which utilizeon-demand rendering, request headers `x-forwarded-proto` and `x-forwarded-port` are insecurely used, without sanitization, to build the URL. This has several consequences, the most important of which are: middleware-based protected route bypass (only via `x-forwarded-proto`), DoS via cache poisoning (if a CDN is present), SSRF (only via `x-forwarded-proto`), URL pollution (potential SXSS, if a CDN is present), and WAF bypass. Version 5.15.5 contains a patch.
CVSS Score
6.5
EPSS Score
0.012
Published
2025-11-13
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