CVE-2026-49411 Deno Node TCPWrap numeric hostname aliases bypass --deny-net resolved-IP deny checks

What is CVE-2026-49411?

CVE-2026-49411 is a medium-severity vulnerability in denoland deno, published on 23 Jun 2026. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

Deno is a JavaScript, TypeScript, and WebAssembly runtime. Prior to 2.8.0, the Node.js compatibility TCP path checked the permission against the original hostname string before resolution and then did not re-check after resolution. A caller could therefore pass a numeric alias of an IP address (for example the decimal integer 2130706433 or the hex form 0x7f000001, both of which resolve to 127.0.0.1) and reach the denied destination through node:net.connect or node:http.request's { host, port } options form. This vulnerability is fixed in 2.8.0.

Weakness: CWE-284

Which versions are affected by CVE-2026-49411?

2 open source packages ship an affected version, including deno. It affects 1 product.

Products include Deno Deno.

How do I fix CVE-2026-49411?

Upgrade deno to 2.8.0 or later.

Is CVE-2026-49411 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-49411 exists.

Other vulnerabilities in denoland deno

• CVE-2023-28445 Deno improperly handles resizable ArrayBuffer Critical 10.0
• CVE-2022-24783 Sandbox bypass leading to arbitrary code execution in Deno Critical 10.0
• CVE-2021-32619 Static imports inside dynamically imported modules do not adhere to permission checks Critical 9.8
• CVE-2026-22863 Deno node:crypto doesn't finalize cipher Critical 9.2
• CVE-2024-27936 Deno interactive permission prompt spoofing via improper ANSI stripping High 8.8

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as GHSA-v8fw-85r8-5m23.