Auth bypass in Denoland Deno

CVE-2026-49983

Deno is a JavaScript, TypeScript, and WebAssembly runtime. Prior to 2.8.1, environment access is gated by the env permission. You can deny it with --deny-env, or restrict it to a specific allowlist with --allow-env=FOO,BAR. The expectation…

Vulnerability class: Broken Access Control

CVSS v3 metric

CVSS v3 base score 5.2 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-49983?
CVE-2026-49983 is a medium-severity vulnerability in Denoland Deno, classified under Incorrect Authorization. CVSS score: 5.2/10. Published 2026-06-23.
How severe is CVE-2026-49983?
Medium severity. CVSS v3 base score is 5.2 out of 10.