Vulnerability in Deno
CVE-2026-49411
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.
EPSS: 0.002 (5.3th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N.
Affected products
- Deno
- Denoland Deno — versions < 2.8.0
Weakness classification (CWE)
References
- security-advisories@github.com (x_refsource_CONFIRM, Exploit, Third Party Advisory, Mitigation)
Frequently asked questions
- What is CVE-2026-49411?
- CVE-2026-49411 is a medium-severity vulnerability in Deno, classified under Improper Access Control. CVSS score: 6.5/10. Published 2026-06-23.
- How severe is CVE-2026-49411?
- Medium severity. CVSS v3 base score is 6.5 out of 10.