CVE-2026-22864

Deno is a JavaScript, TypeScript, and WebAssembly runtime. Before 2.5.6, a prior patch aimed to block spawning Windows batch/shell files by returning an error when a spawned path’s extension matched .bat or .cmd. That check performs a case-sensitive comparison against lowercase literals and therefore can be bypassed when the extension uses alternate casing (for example .BAT, .Bat, etc.). This vulnerability is fixed in 2.5.6.

CVSS v3 8.1 HIGH

8.1^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.2 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/denoland/deno/releases/tag/v2.5.6	Release Notes
https://github.com/denoland/deno/security/advisories/GHSA-m3c4-prhw-mrx6	Exploit Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:deno:deno:*:*:*:*:*:*:*:*

History

21 Jan 2026, 14:32

Type	Values Removed	Values Added
References	~~() https://github.com/denoland/deno/releases/tag/v2.5.6 -~~	() https://github.com/denoland/deno/releases/tag/v2.5.6 - Release Notes
References	~~() https://github.com/denoland/deno/security/advisories/GHSA-m3c4-prhw-mrx6 -~~	() https://github.com/denoland/deno/security/advisories/GHSA-m3c4-prhw-mrx6 - Exploit, Vendor Advisory
First Time		Deno Deno deno
CPE		cpe:2.3:a:deno:deno::::::::

15 Jan 2026, 23:15

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-01-15 23:15

Updated : 2026-01-21 14:32

NVD link : CVE-2026-22864

Mitre link : CVE-2026-22864

CVE.ORG link : CVE-2026-22864

JSON object : View

Products Affected

deno

deno

CWE

CWE-77

Improper Neutralization of Special Elements used in a Command ('Command Injection')

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