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9.8
CRITICAL CVSS 3.1
CVE-2026-22864
Deno has an incomplete fix for command-injection prevention on Windows — case-insensitive extension bypass
Description

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.

INFO

Published Date :

Jan. 15, 2026, 11:15 p.m.

Last Modified :

Jan. 21, 2026, 2:32 p.m.

Remotely Exploit :

Yes !

Source :

[email protected]
Affected Products

The following products are affected by CVE-2026-22864 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Deno deno
: Total Affected Vendor : 1 | Products : 1
CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 HIGH [email protected]
CVSS 3.1 CRITICAL [email protected]
Solution
Update Deno to version 2.5.6 or later to fix the path extension check vulnerability.
  • Update Deno to version 2.5.6 or a newer version.
  • Verify the updated Deno version is applied.
  • Review spawn process configurations for security.
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-22864.

URL 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
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-22864 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-22864 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-22864 vulnerability anywhere in the article.

  • Daily CyberSecurity
CVE-2026-24002: Critical Sandbox Escape Turns Grist Spreadsheets into RCE Weapons

A seemingly innocent spreadsheet formula could be the key to compromising entire organizations, thanks to a critical vulnerability uncovered by Cyera Research Labs in Grist-Core. The flaw, tracked as ... Read more

Published Date: Jan 29, 2026 (1 week ago)
  • Daily CyberSecurity
Critical Deno Flaws Risk Secrets (CVE-2026-22863) & Execution (CVE-2026-22864)

Deno, the modern JavaScript and TypeScript runtime famous for its “secure by default” architecture, has hit a stumbling block with the discovery of two significant security vulnerabilities. The flaws, ... Read more

Published Date: Jan 19, 2026 (2 weeks, 3 days ago)

Results are limited to the first 20 news articles due to potential performance issues.

The following table lists the changes that have been made to the CVE-2026-22864 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • Initial Analysis by [email protected]

    Jan. 21, 2026

    Action Type Old Value New Value
    Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
    Added CPE Configuration OR *cpe:2.3:a:deno:deno:*:*:*:*:*:*:*:* versions up to (excluding) 2.5.6
    Added Reference Type GitHub, Inc.: https://github.com/denoland/deno/releases/tag/v2.5.6 Types: Release Notes
    Added Reference Type GitHub, Inc.: https://github.com/denoland/deno/security/advisories/GHSA-m3c4-prhw-mrx6 Types: Exploit, Vendor Advisory
  • New CVE Received by [email protected]

    Jan. 15, 2026

    Action Type Old Value New Value
    Added Description 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.
    Added CVSS V3.1 AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
    Added CWE CWE-77
    Added Reference https://github.com/denoland/deno/releases/tag/v2.5.6
    Added Reference https://github.com/denoland/deno/security/advisories/GHSA-m3c4-prhw-mrx6
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.
Vulnerability Scoring Details
Base CVSS Score: 9.8
Attack Vector
Attack Complexity
Privileges Required
User Interaction
Scope
Confidentiality Impact
Integrity Impact
Availability Impact