CVE-2026-49402

Deno: Command Injection via spawnSync & spawn on Windows

Deno is a JavaScript, TypeScript, and WebAssembly runtime. Prior to 2.7.10, Deno's node:child_process implementation provided an escapeShellArg() helper used when callers passed shell: true to spawn / spawnSync / exec and friends. On Windows, the helper failed to quote arguments that contained cmd.exe metacharacters and did not neutralize % (which cmd.exe expands even inside double-quoted strings). An attacker who controlled any portion of an argument passed to such a call could inject arbitrary additional commands into the spawned cmd.exe invocation. This vulnerability is fixed in 2.7.10.

Affected

denoland · deno

CVSS v3.1 NVD

8.1 HIGHCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

EPSS

0.45% chance of exploitation in the next 30 days, 37th percentile

Published

2026-06-23

Updated

2026-06-25

Proof-of-concept exploits (1)

• advisories/GHSA-7xh3-mhg9-jcw8

Security advisories

• denoland/deno/security/advisories/GHSA-7xh3-mhg9-jcw8

References

• CVE Record
• NVD entry