Security Advisory

CVE-2026-49860

CVE vulnerability detail - eXtreme Datacenter Security Operations

Published 2026-06-23 17:15:05
Last updated 2026-06-23 17:37:07
Assigner GitHub_M
CVSS score 5.2
State PUBLISHED

Description

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.