PT-2026-35036 · Julia · Deno Jll

Published 2026-04-14 · Updated 2026-04-14

OSV

CVSS v3.1

7.7

High

Base vector

AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

Deno is a JavaScript, TypeScript, and WebAssembly runtime with secure defaults. By using ANSI escape sequences and a race between libc::tcflush(0, libc::TCIFLUSH) and reading standard input, it's possible to manipulate the permission prompt and force it to allow an unsafe action regardless of the user input. Some ANSI escape sequences act as a info request to the master terminal emulator and the terminal emulator sends back the reply in the PTY channel. standard streams also use this channel to send and get data. For example the 033[6n sequence requests the current cursor position. These sequences allow us to append data to the standard input of Deno. This vulnerability allows an attacker to bypass Deno permission policy. This vulnerability is fixed in 1.42.2.

Fix

Related Identifiers

JLSEC-2026-106

Affected Products

Deno Jll

References · 2

• https://osv.dev/vulnerability/JLSEC-2026-106 · Vendor Advisory
• https://github.com/denoland/deno/security/advisories/GHSA-95cj-3hr2-7j5j · Note