High 8.1Published Jan 15, 2026

CVE-2026-22864Deno has an incomplete fix for command-injection prevention on Windows — case-insensitive extension bypass

Updated under an hour ago (Oct 27, 2026, 4:50 AM ET)

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Every CVE for denoland deno

Exploited in the last 30 days

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: 8.1 HIGH (v3.1, CNA)CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
Weakness (CWE): CWE-77
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: GitHub_M
NVD analysis: Analyzed
Record last updated: Jan 16, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

denoland deno denoland:deno (from the name)	before 2.5.6	CNA record
deno deno deno:deno	before 2.5.6	NVD

References

References

https://github.com/denoland/deno/security/advisories/GHSA-m3c4-prhw-mrx6	x-refsource-confirm, exploit, vendor-advisory
https://github.com/denoland/deno/releases/tag/v2.5.6	x-refsource-misc, release-notes

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.