{"id":"CVE-2026-27829","state":"PUBLISHED","title":"Astro is vulnerable to SSRF due to missing allowlist enforcement in remote image inferSize","description":"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.","publishedAt":"2026-02-26T00:36:40.497Z","updatedAt":"2026-02-26T16:21:44.676Z","severity":{"score":6.5,"label":"Medium","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L","source":"GitHub_M"},"assigner":"GitHub_M","products":["withastro astro"],"affected":[{"vendor":"withastro","product":"astro","versions":[{"version":">= 9.0.0, < 9.5.4","status":"affected"}]}],"references":["https://github.com/withastro/astro/security/advisories/GHSA-cj9f-h6r6-4cx2","https://github.com/withastro/astro/commit/e01e98b063e90d274c42130ec2a60cc0966622c9"],"weaknesses":["CWE-918"],"ingestedAt":"2026-10-29T20:11:31.369Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/27xxx/CVE-2026-27829.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-27829","state":"PUBLISHED","datePublished":"2026-02-26T00:36:40.497Z","dateUpdated":"2026-02-26T16:21:44.676Z","assignerShortName":"GitHub_M","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateReserved":"2026-02-24T02:32:39.800Z"},"containers":{"cna":{"title":"Astro is vulnerable to SSRF due to missing allowlist enforcement in remote image inferSize","descriptions":[{"lang":"en","value":"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."}],"affected":[{"vendor":"withastro","product":"astro","versions":[{"version":">= 9.0.0, < 9.5.4","status":"affected"}]}],"references":[{"url":"https://github.com/withastro/astro/security/advisories/GHSA-cj9f-h6r6-4cx2","name":"https://github.com/withastro/astro/security/advisories/GHSA-cj9f-h6r6-4cx2","tags":["x_refsource_CONFIRM"]},{"url":"https://github.com/withastro/astro/commit/e01e98b063e90d274c42130ec2a60cc0966622c9","name":"https://github.com/withastro/astro/commit/e01e98b063e90d274c42130ec2a60cc0966622c9","tags":["x_refsource_MISC"]}],"metrics":[{"cvssV3_1":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"LOW","baseScore":6.5,"baseSeverity":"MEDIUM","confidentialityImpact":"NONE","integrityImpact":"LOW","privilegesRequired":"NONE","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L","version":"3.1"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-918","lang":"en","description":"CWE-918: Server-Side Request Forgery (SSRF)","type":"CWE"}]}],"providerMetadata":{"shortName":"GitHub_M","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateUpdated":"2026-02-26T00:36:40.497Z"},"source":{"advisory":"GHSA-cj9f-h6r6-4cx2","discovery":"UNKNOWN"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-02-26T16:21:28.348418Z","id":"CVE-2026-27829","options":[{"Exploitation":"poc"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-02-26T16:21:44.676Z"}}]}}}