CVE-2026-22864
HIGHDeno < 2.5.6 - Command Injection via Case-Insensitive Extension Bypass
Title source: llmDescription
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.
References (2)
Core 2
Core References
Exploit, Vendor Advisory x_refsource_confirm
https://github.com/denoland/deno/security/advisories/GHSA-m3c4-prhw-mrx6
Release Notes x_refsource_misc
https://github.com/denoland/deno/releases/tag/v2.5.6
Scores
CVSS v3
8.1
EPSS
0.0062
EPSS Percentile
44.9%
Attack Vector
NETWORK
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
CISA SSVC
Vulnrichment
Exploitation
none
Automatable
no
Technical Impact
total
Details
CWE
CWE-77
Status
published
Products (2)
crates.io/deno
0 - 2.5.6crates.io
deno/deno
< 2.5.6
Published
Jan 15, 2026
Tracked Since
Feb 18, 2026