GoKawiil2024 critique argues Deno's permission system offers only superficial sandboxing
A developer published a 2024 post examining Deno's permissions system, which lets users grant JavaScript programs specific access rights like file reads or subprocess execution via flags such as --allow-read, or through runtime prompts that ask users to approve or deny access. The author argues this model, despite being marketed as 'secure by default,' has structural weaknesses that undermine its effectiveness as a security boundary.
GoKawiil's interpretation of the reporting above, not reported fact.
The critique suggests that permission prompts and command-line flags can create a false sense of safety if users habitually approve requests without understanding their scope, which could let malicious or compromised packages still gain meaningful access. This matters because Deno positions its security model as a key differentiator from Node.js, so flaws here could affect developer trust in using Deno for untrusted or third-party code. The author's framing implies the problem may be fundamental to permission-prompt approaches generally, not just a minor implementation detail.
- Deno's permission system lets developers restrict JS programs' access to files, network, and subprocesses via flags or runtime prompts.
- The author argues the model is 'fundamentally insecure and misleading' despite being advertised as 'secure by default.'
- The critique focuses partly on a 'prompts problem,' suggesting runtime permission requests can be bypassed or misused.
Source: goldstein.lol, 2026-11-08
Published there as: “I'm not a fan of Deno's security model (2024)”
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