Deno vulnerable to command Injection via incomplete shell metacharacter blocklist in node:child_process

Exploitation

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

CVSS

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

EPSS

• CVE-2026-32260: 1.54% estimated exploitation activity in the next 30 days; percentile 74.97 (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.

Summary A command injection vulnerability exists in Deno's node:childprocess polyfill (shell: true mode) that bypasses the fix for CVE-2026-27190 (GHSA-hmh4-3xvx-q5hr). An attacker who controls arguments passed to spawnSync or spawn with shell: true can execute arbitrary OS commands, bypassing Deno's permission system. Affected versions: Deno v2.7.0, v2.7.1

Details The two-stage argument sanitization in transformDenoShellCommand (ext/node/polyfills/internal/childprocess.ts) has a priority bug: when an argument contains a $VAR pattern, it is wrapped in double quotes (L1290) instead of single quotes (L1293). Double quotes in POSIX sh do not suppress backtick command substitution, allowing injected commands to execute. Attack chain: 1. escapeShellArg wraps the argument in single quotes (safe) 2. opnodeparseshellargs strips the single-quote delimiters during tokenization (raw argument exposed) 3. Re-quoting detects $VAR pattern → applies double quotes 4. Backtick payload inside double…

Published by the source

13 Mar 2026, 20:02 UTC

Last modified by the source

13 Mar 2026, 20:02 UTC

Source last checked

26 Oct 2026, 15:42 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-4c96-w8v2-p28j

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# Patch Next advisory brief: CVE-2026-32260

Advisory: Deno vulnerable to command Injection via incomplete shell metacharacter blocklist in node:child_process
IDs: CVE-2026-32260, GHSA-4c96-w8v2-p28j
Record: https://patchnext.com/advisories/cve-2026-32260 (revision 1, source checked 26 Oct 2026, 15:42 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: High (CVSS 8.1)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: deno 2.7.2. A vendor fix does not mean a deployment is fixed.

## Affected components
- crates.io deno: affected >= 2.7.0, < 2.7.2; fixed in 2.7.2

## Suggested inspection (read-only)
- crates.io deno: check the installed version with your package manager.

## 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 deno.
- 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://github.com/advisories/GHSA-4c96-w8v2-p28j (GitHub-reviewed advisory GHSA-4c96-w8v2-p28j lists affected ranges: crates.io deno >=2.7.0 <2.7.2)

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