Vulnerability · Published Jun 23, 2026 · Assigned by GitHub_M

CVE-2026-49401Deno Permission Bypass via Unicode Normalization Mismatch on macOS (APFS)

High 7.3

In plain English

A high-severity security flaw in deno from denoland. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 9% of all known vulnerabilities).

Severity (CVSS 3.1)7.3High
Exploit odds (30 days)0.2%top 90.5% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known

Official description

Deno is a JavaScript, TypeScript, and WebAssembly runtime. Prior to 2.7.14, Deno's permission system enforces filesystem and execution restrictions by comparing the requested path against the path supplied to --deny-read, --deny-write, --deny-run, or --deny-ffi. On macOS, that comparison was done at the raw-byte level while the APFS filesystem treats different Unicode spellings of the same name as the same file. That means a program could reach a denied path by spelling it differently than the deny rule. This vulnerability is fixed in 2.7.14.

Affected products (as reported)

VendorProductVersions
denoland deno < 2.7.14

Weakness: CWE-41, CWE-176 · Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:L/I:H/A:N

References