{"id":"CVE-2026-49860","sourceIdentifier":"security-advisories@github.com","published":"2026-06-23T18:18:04.053","lastModified":"2026-06-29T14:37:08.490","vulnStatus":"Analyzed","cveTags":[],"descriptions":[{"lang":"en","value":"Deno is a JavaScript, TypeScript, and WebAssembly runtime. Prior to 2.8.1, when a WebSocket connection was opened, Deno checked the destination hostname against --deny-net rules but did not re-check the IP addresses that hostname resolved to. An attacker-controlled script could use a specially crafted domain name that passes the hostname check yet resolves to a denied IP, bypassing the network restriction entirely. This vulnerability is fixed in 2.8.1."}],"affected":[{"source":"security-advisories@github.com","affectedData":[{"vendor":"denoland","product":"deno","versions":[{"version":"< 2.8.1","status":"affected"}]}]}],"metrics":{"cvssMetricV31":[{"source":"security-advisories@github.com","type":"Secondary","cvssData":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N","baseScore":5.2,"baseSeverity":"MEDIUM","attackVector":"LOCAL","attackComplexity":"LOW","privilegesRequired":"LOW","userInteraction":"NONE","scope":"CHANGED","confidentialityImpact":"LOW","integrityImpact":"LOW","availabilityImpact":"NONE"},"exploitabilityScore":2.0,"impactScore":2.7}],"ssvcV203":[{"source":"134c704f-9b21-4f2e-91b3-4a467353bcc0","ssvcData":{"timestamp":"2026-06-23T17:37:00.680109Z","id":"CVE-2026-49860","options":[{"exploitation":"none"},{"automatable":"no"},{"technicalImpact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}]},"weaknesses":[{"source":"security-advisories@github.com","type":"Primary","description":[{"lang":"en","value":"CWE-918"}]}],"configurations":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:a:deno:deno:*:*:*:*:*:*:*:*","versionEndExcluding":"2.8.1","matchCriteriaId":"91F453C2-277C-4350-8234-700B47587E97"}]}]}],"references":[{"url":"https://github.com/denoland/deno/security/advisories/GHSA-83pc-3rw9-qpwj","source":"security-advisories@github.com","tags":["Vendor Advisory"]}]}