VULNERABILITY INTELLIGENCE

CVE-2026-49860

CVSS score5.2 MEDIUM
EPSS probability0.14%
CISA KEVNot currently listed
Published2026-06-23
Last modified2026-10-25
CVSS vectorCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N

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.

Weakness classification

  • security-advisories@github.com: CWE-918

Primary references