{"id":"CVE-2026-44726","revision":"cfcda5b82b1f4571b09bd2657149c274","records":[{"revision":"cfcda5b82b1f4571b09bd2657149c274","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-44726","aliases":[],"title":"Deno: TLS retry copies stale upgrade hook, risking plaintext traffic","description":"Deno is a JavaScript, TypeScript, and WebAssembly runtime. From 2.0.0 until 2.7.8, a flaw in Deno's Node.js tls compatibility layer could cause a TLS client to transmit application data in plaintext after a connection retry. When `autoSelectFamily was enabled and the first address-family attempt failed, the socket reinitialization path reused a stale TLS upgrade hook that was bound to the original, failed handle. As a result, the replacement TCP connection was never upgraded to TLS, and any data the application wrote before the secureConnect event travelled over the network unencrypted. A network attacker positioned to cause the initial connection attempt to fail (for example, by dropping IPv6 traffic on a dual-stack host) could deterministically trigger the fallback path and observe or tamper with traffic that the application believed was TLS-protected. This vulnerability is fixed in 2.7.8.","state":0,"publishedAt":"2026-06-23T17:24:02.702+00:00","modifiedAt":"2026-06-25T13:48:50.17+00:00","affected":[{"ecosystem":"Vendor product","name":"deno","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"vendor\": \"denoland\",\n                    \"product\": \"deno\",\n                    \"versions\": [\n                        {\n                            \"version\": \">= 2.0.0, < 2.7.8\",\n                            \"status\": \"affected\"\n                        }\n                    ]\n                }"}],"metrics":[{"system":"CVSS 3.1","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N","score":7.4,"severity":"HIGH"}],"references":["https://github.com/denoland/deno/security/advisories/GHSA-chqv-56wv-7564"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-44726","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-44726","identifiers":["CVE-2026-44726"]},"retained":false,"historicalAffected":[]}],"coverage":[]}