CVE-2026-49406: Deno

Medium severity, CVSS 5.5. EPSS: 0.2% chance of exploitation in the next 30 days.

Deno is a JavaScript, TypeScript, and WebAssembly runtime. Prior to 2.7.12, when Deno was run in BYONM mode (nodeModulesDir: "manual"), the module resolver did not validate that a package's resolved entrypoint stayed within its node_modules/<pkg>/ directory. A malicious package.json whose main field contained .. segments was able to resolve to an arbitrary path on disk, and the resolver then read that file without consulting the --allow-read allowlist. This let a require("evil-pkg") call return the contents of a file that a direct Deno.readTextFileSync(...) call would have been blocked from reading. This vulnerability is fixed in 2.7.12.

Affected products

• Deno Deno: before 2.7.12 (fixed in 2.7.12)

Published 2026-06-23. Last modified 2026-06-26.