Shescape potential environment variable exposure on Windows with CMD

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

3.1 · CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:N/A:N

EPSS

• CVE-2023-35931: 0.81% estimated exploitation activity in the next 30 days; percentile 56.98 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Impact This impact users of Shescape: 1. On Windows using the Windows Command Prompt (i.e. cmd.exe), and 2. Using quote/quoteAll or escape/escapeAll with the interpolation option set to true. An attacker may be able to get read-only access to environment variables. Example: Patches This bug has been patched in v1.7.1 which you can upgrade to now. No further changes are required. Workarounds Alternatively, users can remove all instances of % from user input, either before or after using Shescape. References - Shescape Pull request #982 - Shescape commit d0fce70 - Shescape Release v1.7.1

Published by the source

22 Jun 2023, 20:01 UTC

Last modified by the source

10 Sep 2026, 03:50 UTC

Source last checked

26 Oct 2026, 12:27 UTC

1. Revision 2 · amended · 26 Oct 2026

   Amended from ghsa record GHSA-3g7p-8qhx-mc8r

2. Revision 1 · created · 24 Oct 2026

   Published from osv record GHSA-3g7p-8qhx-mc8r

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# Patch Next advisory brief: CVE-2023-35931

Advisory: Shescape potential environment variable exposure on Windows with CMD
IDs: CVE-2023-35931, GHSA-3g7p-8qhx-mc8r
Record: https://patchnext.com/advisories/cve-2023-35931 (revision 2, source checked 26 Oct 2026, 12:27 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Low (CVSS 3.1)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: shescape 1.7.1. A vendor fix does not mean a deployment is fixed.

## Affected components
- npm shescape: affected < 1.7.1; fixed in 1.7.1

## Suggested inspection (read-only)
- `npm ls shescape --all`: lists every installed copy and version, including transitive ones. Run in the project root after `npm ci`.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on shescape.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://osv.dev/vulnerability/GHSA-3g7p-8qhx-mc8r (OSV record GHSA-3g7p-8qhx-mc8r lists affected ranges: npm shescape >=0 <1.7.1 (fixed))
- Verified: https://github.com/advisories/GHSA-3g7p-8qhx-mc8r (GitHub-reviewed advisory GHSA-3g7p-8qhx-mc8r lists affected ranges: npm shescape >=0 <1.7.1)

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