CVE-2026-55517

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{"affected": [{"affectedData": [{"product": "deno", "vendor": "denoland", "versions": [{"status": "affected", "version": "< 2.7.5"}]}], "source": "security-advisories@github.com"}], "configurations": [{"nodes": [{"cpeMatch": [{"criteria": "cpe:2.3:a:deno:deno:*:*:*:*:*:*:*:*", "matchCriteriaId": "D23838A8-D7D0-462F-8B7D-C33526ABD5FB", "versionEndExcluding": "2.7.5", "vulnerable": true}], "negate": false, "operator": "OR"}]}], "cveTags": [], "descriptions": [{"lang": "en", "value": "Deno is a JavaScript, TypeScript, and WebAssembly runtime. Prior to 2.7.5, a Deno program that opens a client WebSocket connection could be crashed by the remote server. While handling the WebSocket handshake response, Deno parsed the Sec-WebSocket-Protocol and Sec-WebSocket-Extensions response headers in a way that assumed their bytes were always printable ASCII. A response header containing non-visible-ASCII bytes (0x80-0xFF) caused a panic that aborted the entire Deno process. This vulnerability is fixed in 2.7.5."}, {"lang": "es", "value": "Deno es un entorno de ejecuci\u00f3n de JavaScript, TypeScript y WebAssembly. Antes de la versi\u00f3n 2.7.5, un programa Deno que abr\u00eda una conexi\u00f3n WebSocket de cliente pod\u00eda ser colapsado por el servidor remoto. Al manejar la respuesta de handshake de WebSocket, Deno analizaba los encabezados de respuesta Sec-WebSocket-Protocol y Sec-WebSocket-Extensions de una manera que asum\u00eda que sus bytes eran siempre ASCII imprimibles. Un encabezado de respuesta que conten\u00eda bytes ASCII no visibles (0x80-0xFF) causaba un p\u00e1nico que abortaba todo el proceso Deno. Esta vulnerabilidad est\u00e1 corregida en la versi\u00f3n 2.7.5."}], "id": "CVE-2026-55517", "lastModified": "2026-10-25T23:10:00.167", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "LOW", "baseScore": 4.3, "baseSeverity": "MEDIUM", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "REQUIRED", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L", "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-2026-55517", "options": [{"exploitation": "none"}, {"automatable": "no"}, {"technicalImpact": "partial"}], "role": "CISA Coordinator", "timestamp": "2026-06-23T17:52:15.311461Z", "version": "2.0.3"}}]}, "published": "2026-06-23T18:18:09.787", "references": [{"source": "security-advisories@github.com", "tags": ["Mitigation", "Vendor Advisory"], "url": "https://github.com/denoland/deno/security/advisories/GHSA-x2qc-cmh9-f4hf"}], "sourceIdentifier": "security-advisories@github.com", "vulnStatus": "Analyzed", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-248"}], "source": "security-advisories@github.com", "type": "Primary"}]}

{}

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