CVE-2026-46431

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{"affected": [{"affectedData": [{"product": "algernon", "vendor": "xyproto", "versions": [{"status": "affected", "version": "< 1.17.7"}]}], "source": "security-advisories@github.com"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "Algernon is a small self-contained pure-Go web server. Prior to 1.17.7, the SSE event server's Access-Control-Allow-Origin response header was hardcoded to the wildcard * regardless of the caller's Origin. Because EventSource does not preflight and does not send cookies, the wildcard is sufficient to let any third-party page the developer visits open a cross-origin EventSource to the SSE port and read the live filename stream from JavaScript. This vulnerability is fixed in 1.17.7."}, {"lang": "es", "value": "Algernon es un peque\u00f1o servidor web autocontenido pure-Go. Antes de la 1.17.7, el encabezado de respuesta Access-Control-Allow-Origin del servidor de eventos SSE estaba codificado de forma r\u00edgida al comod\u00edn * independientemente del Origin del llamador. Debido a que EventSource no realiza una solicitud de pre-vuelo y no env\u00eda cookies, el comod\u00edn es suficiente para permitir que cualquier p\u00e1gina de terceros que el desarrollador visite abra un EventSource de origen cruzado al puerto SSE y lea el flujo de nombres de archivo en vivo desde JavaScript. Esta vulnerabilidad est\u00e1 corregida en la 1.17.7."}], "id": "CVE-2026-46431", "lastModified": "2026-07-24T11:10:00.170", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "NONE", "baseScore": 4.3, "baseSeverity": "MEDIUM", "confidentialityImpact": "LOW", "integrityImpact": "NONE", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "REQUIRED", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N", "version": "3.1"}, "exploitabilityScore": 2.8, "impactScore": 1.4, "source": "security-advisories@github.com", "type": "Secondary"}], "ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-46431", "options": [{"exploitation": "poc"}, {"automatable": "no"}, {"technicalImpact": "partial"}], "role": "CISA Coordinator", "timestamp": "2026-05-26T17:38:47.158630Z", "version": "2.0.3"}}]}, "published": "2026-05-26T17:16:51.100", "references": [{"source": "security-advisories@github.com", "url": "https://github.com/xyproto/algernon/security/advisories/GHSA-hw27-4v2q-5qff"}, {"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "url": "https://github.com/xyproto/algernon/security/advisories/GHSA-hw27-4v2q-5qff"}], "sourceIdentifier": "security-advisories@github.com", "vulnStatus": "Deferred", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-942"}], "source": "security-advisories@github.com", "type": "Secondary"}]}

{}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[0,1.17.7)"}}], "enrichment": {"confidence": 100.0, "confidence_source": "cna", "scores": [{"score": 100.0, "source": "cna"}]}, "original": {"product": "algernon", "source": "cna", "vendor": "xyproto"}, "product": "algernon", "vendor": "xyproto"}], "created": "2026-05-26T18:45:13.153697+00:00", "updated": "2026-05-27T10:04:42.538203+00:00", "vendors": ["xyproto", "xyproto$PRODUCT$algernon"]}