CVE-2025-55303 — Unauthorized third-party images in Astro’s _image endpoint
Astro is a web framework for content-driven websites. In versions of astro before 5.13.2 and 4.16.18, the image optimization endpoint in projects deployed with on-demand renderi…
Published: 2025-08-19 · CVSS: 6.9 · CVSS 4.0
Astro is a web framework for content-driven websites. In versions of astro before 5.13.2 and 4.16.18, the image optimization endpoint in projects deployed with on-demand rendering allows images from unauthorized third-party domains to be served. On-demand rendered sites built with Astro include an /_image endpoint which returns optimized versions of images. A bug in impacted versions of astro allows an attacker to bypass the third-party domain restrictions by using a protocol-relative URL as the image source, e.g. /_image?href=//example.com/image.png. This vulnerability is fixed in 5.13.2 and 4.16.18.
Source: CVE Program · Revision 8b16575c39f1e1810c5e863010da073d2d3285e7