{"id":"CVE-2026-27829","summary":"Astro is vulnerable to SSRF due to missing allowlist enforcement in remote image inferSize","details":"Astro is a web framework. In versions 9.0.0 through 9.5.3, a bug in Astro's image pipeline allows bypassing `image.domains` / `image.remotePatterns` restrictions, enabling the server to fetch content from unauthorized remote hosts. Astro provides an `inferSize` option that fetches remote images at render time to determine their dimensions. Remote image fetches are intended to be restricted to domains the site developer has manually authorized (using the `image.domains` or `image.remotePatterns` options). However, when `inferSize` is used, no domain validation is performed — the image is fetched from any host regardless of the configured restrictions. An attacker who can influence the image URL (e.g., via CMS content or user-supplied data) can cause the server to fetch from arbitrary hosts. This allows bypassing `image.domains` / `image.remotePatterns` restrictions to make server-side requests to unauthorized hosts. This includes the risk of server-side request forgery (SSRF) against internal network services and cloud metadata endpoints. Version 9.5.4 fixes the issue.","aliases":["GHSA-cj9f-h6r6-4cx2"],"modified":"2026-08-12T03:51:42.027968638Z","published":"2026-02-26T00:36:40.497Z","database_specific":{"cwe_ids":["CWE-918"],"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/27xxx/CVE-2026-27829.json","cna_assigner":"GitHub_M"},"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/27xxx/CVE-2026-27829.json"},{"type":"ADVISORY","url":"https://github.com/withastro/astro/security/advisories/GHSA-cj9f-h6r6-4cx2"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-27829"},{"type":"FIX","url":"https://github.com/withastro/astro/commit/e01e98b063e90d274c42130ec2a60cc0966622c9"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/withastro/astro","events":[{"introduced":"f55ba4caca7c587555da86e3211ae1f1b3407c5f"},{"fixed":"e0f1a2b3e4bc908bd5e148c698efb6f41a42c8ea"},{"fixed":"e01e98b063e90d274c42130ec2a60cc0966622c9"}],"database_specific":{"cpe":"cpe:2.3:a:astro:\\@astrojs\\/node:*:*:*:*:*:node.js:*:*","extracted_events":[{"introduced":"9.0.0"},{"fixed":"9.5.4"}],"source":["CPE_RANGE","REFERENCES"]}}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-27829.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L"}]}