Vulnerabilities in pkg:npm/shescape

PACKAGE
Advisory Identifier: GHSA-w4hw-qcx7-56pr
Advisory Summary

CVE-2026-73414 is a CRITICAL shell injection vulnerability (CWE-78: Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')) affecting Shescape libraries in the npm ecosystem. The issue involves shell injection via unescaped parentheses on windows with cmd. Remediation is available by upgrading affected packages to version 2.1.14, 3.0.1.

14 Known Advisory Record(s)
Package Vulnerability Intelligence

pkg:npm/shescape

14 Known Advisory Record(s)

Vulnerability advisories affecting package pkg:npm/shescape. Select an advisory below to view technical details or fixes.

Advisory ID CVE / NVD Severity Summary
GHSA-w4hw-qcx7-56pr CVE-2026-73414 CRITICAL Shescape: Shell injection via unescaped parentheses on Windows with CMD
GHSA-gm3r-q2wp-hw87 CVE-2026-73413 HIGH Shescape: Quadratic-time denial of service in the flag-protection
GHSA-6v4m-fw66-8r4x CVE-2026-73412 MODERATE Shescape: Path disclosure on Unix with Zsh
GHSA-q53c-4prm-w95q CVE-2026-73411 MODERATE Shescape: Home-directory disclosure in assignment context on Unix with Dash
GHSA-6f6w-6j58-rq76 CVE-2026-30916 LOW Withdrawn Advisory: Shescape has possible misidentification of shell due to link chains
GHSA-9jfh-9xrq-4vwm CVE-2026-32094 MODERATE Shescape escape() leaves bracket glob expansion active on Bash, BusyBox, and Dash
GHSA-66pp-5p9w-q87j CVE-2025-30222 LOW Shescape has potential environment variable exposure on Windows with CMD
GHSA-j55r-787p-m549 CVE-2023-40185 HIGH Shescape on Windows escaping may be bypassed in threaded context
GHSA-3g7p-8qhx-mc8r CVE-2023-35931 LOW Shescape potential environment variable exposure on Windows with CMD
GHSA-cr84-xvw4-qx3c CVE-2022-25918 HIGH Inefficient Regular Expression Complexity in shescape
GHSA-44vr-rwwj-p88h CVE-2022-31180 CRITICAL Shescape vulnerable to insufficient escaping of whitespace
GHSA-jjc5-fp7p-6f8w CVE-2022-31179 HIGH Shescape prior to 1.5.8 vulnerable to insufficient escaping of line feeds for CMD
GHSA-446w-rrm4-r47f CVE-2022-24725 MODERATE Exposure of home directory through shescape on Unix with Bash
GHSA-f2rp-38vg-j3gh CVE-2021-21384 HIGH Null characters not escaped

CVE-2026-73414 at a Glance

CVE Identifier CVE-2026-73414
GHSA Identifier GHSA-w4hw-qcx7-56pr
Severity CRITICAL
CVSS v3.1 Base Score N/A
CWE Classification CWE-78: Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')
Affected Product Shescape
Package Ecosystem npm
Published Date
Last Updated

How to Fix CVE-2026-73414

To remediate this vulnerability, upgrade all affected Shescape dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

shescape fixed: 2.1.14
npm install shescape@2.1.14
shescape fixed: 3.0.1
npm install shescape@3.0.1
Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release:

npm ls shescape

How to Check if You Are Affected

To determine whether your Node.js application is affected by CVE-2026-73414, inspect your project dependencies using npm:

npm ls shescape

Analyze the terminal output to locate any version of Shescape in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 2.1.14), your application is affected.

Note: The npm ls shescape command inspects dependencies declared in your package.json and lockfile; it does not perform automated runtime dynamic scanning.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-78: Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection'), where the product constructs all or part of an os command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended os command when it is sent to a downstream component. In Shescape, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.

Source Advisory Statement

### Impact This impacts users of Shescape on Windows that explicitly configure `shell` to CMD, or `true` with the default shell being CMD, using the `escape` and `escapeAll` APIs. An attacker may be able to achieve shell injection depending on the original command. ```javascript import * as cp from "node:child_process"; import { Shescape } from "shescape"; // 1. Prerequisites const options = { shell: "cmd.exe", // Or shell: true, // Only if the default shell is CMD }; // 2. Payload const payload = "x) else if a==a (echo y"; // 3. Usage const shescape = new Shescape(options); let escapedPayload; escapedPayload = shescape.escape(payload); // Or escapedPayload = shescape.escapeAll([payload]); // And (example) const result = cp.execSync(`if defined FALSY (echo ${escapedPayload})`, options); // 4. Impact console.log(result.toString()); // Outputs "y" instead of "" ``` ### Patches This bug has been patched in [v2.1.14] and [v3.0.1] which you can upgrade to now. If you are already using v3 of Shescape, no further changes are required. If you are using v2 of Shescape is recommended to upgrade as this version reaches end-of-life status on 2026-09-28, follow the [migration guide] to upgrade to v3. No patches will be released for version of Shescape lower than v2.0.0. ### Workarounds Alternatively, users of Shescape can remove all instances of `(` and `)` from untrusted inputs. ### For more information - Comment on Pull Request [#2651] for v2 and [#2649] for v3 - Comment on commit [b4b34c3] for v2 and [43d70b5] for v3 - Open an issue at <https://github.com/ericcornelissen/shescape/issues> (New issue > Question)

CVE-2026-73414 Affected Shescape Versions

2 component(s)
Fixed Versions:
2.1.143.0.1
Product / Package Ecosystem Affected Versions Fixed Version
shescape
npm
< 2.1.14
2.1.14
shescape
npm
≥ 3.0.0
< 3.0.1
3.0.1

References

Frequently Asked Questions

What is CVE-2026-73414?
CVE-2026-73414 is a security vulnerability in Shescape involving Shell injection via unescaped parentheses on Windows with CMD under CWE-78: Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection').
Which Shescape versions are affected?
Affected versions include releases prior to 2.1.14, 3.0.1 across affected packages: shescape.
What version fixes CVE-2026-73414?
Upgrading to 2.1.14, 3.0.1 (or the latest patched release for your respective branch) resolves the vulnerability.
Is shescape affected?
Yes, shescape is affected in releases prior to 2.1.14, 3.0.1. Upgrade your dependency to 2.1.14, 3.0.1 or later.
What CWE is associated with CVE-2026-73414?
CVE-2026-73414 is classified under CWE-78: Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection') (The product constructs all or part of an OS command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended OS command when it is sent to a downstream component.).
How can I check npm dependencies for CVE-2026-73414?
Run the dependency tree command: 'npm ls shescape'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.
Machine-readable OSV JSON OSV v1.5 Schema
Normalized schema output
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-w4hw-qcx7-56pr",
  "modified" : "2026-08-12T19:43:04Z",
  "published" : "2026-07-24T22:34:23Z",
  "aliases" : [ "CVE-2026-73414" ],
  "summary" : "Shescape: Shell injection via unescaped parentheses on Windows with CMD",
  "details" : "### Impact\n\nThis impacts users of Shescape on Windows that explicitly configure `shell` to CMD, or `true` with the default shell being CMD, using the `escape` and `escapeAll` APIs.\n\nAn attacker may be able to achieve shell injection depending on the original command.\n\n```javascript\nimport * as cp from \"node:child_process\";\nimport { Shescape } from \"shescape\";\n\n// 1. Prerequisites\nconst options = {\n    shell: \"cmd.exe\",\n    // Or\n    shell: true, // Only if the default shell is CMD\n};\n\n// 2. Payload\nconst payload = \"x) else if a==a (echo y\";\n\n// 3. Usage\nconst shescape = new Shescape(options);\nlet escapedPayload;\n\nescapedPayload = shescape.escape(payload);\n// Or\nescapedPayload = shescape.escapeAll([payload]);\n\n// And (example)\nconst result = cp.execSync(`if defined FALSY (echo ${escapedPayload})`, options);\n\n// 4. Impact\nconsole.log(result.toString());\n// Outputs \"y\" instead of \"\"\n\n```\n\n### Patches\n\nThis bug has been patched in [v2.1.14] and [v3.0.1] which you can upgrade to now.\n\nIf you are already using v3 of Shescape, no further changes are required. If you are using v2 of Shescape is recommended to upgrade as this version reaches end-of-life status on 2026-09-28, follow the [migration guide] to upgrade to v3.\n\nNo patches will be released for version of Shescape lower than v2.0.0.\n\n### Workarounds\n\nAlternatively, users of Shescape can remove all instances of `(` and `)` from untrusted inputs.\n\n### For more information\n\n- Comment on Pull Request [#2651] for v2 and [#2649] for v3\n- Comment on commit [b4b34c3] for v2 and [43d70b5] for v3\n- Open an issue at <https://github.com/ericcornelissen/shescape/issues> (New issue > Question)",
  "severity" : [ {
    "type" : "CVSS_V4",
    "score" : "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "npm",
      "name" : "shescape"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "2.1.14"
      } ]
    } ]
  }, {
    "package" : {
      "ecosystem" : "npm",
      "name" : "shescape"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "3.0.0"
      }, {
        "fixed" : "3.0.1"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/ericcornelissen/shescape/security/advisories/GHSA-w4hw-qcx7-56pr"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/ericcornelissen/shescape/pull/2649"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/ericcornelissen/shescape/pull/2651"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/ericcornelissen/shescape/commit/43d70b59d09bbe5c3fd02ef08b3a123e977ed9de"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/ericcornelissen/shescape/commit/b4b34c394e7f9da2775bb75381066b9a228c425f"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/ericcornelissen/shescape"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/ericcornelissen/shescape/blob/dea8893a5877893d8d4923dbf253080e08899e6d/docs/migration.md"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/ericcornelissen/shescape/releases/tag/v2.1.14"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/ericcornelissen/shescape/releases/tag/v3.0.1"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-150", "CWE-78" ],
    "severity" : "CRITICAL",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-07-24T22:34:23Z",
    "nvd_published_at" : null
  }
}