GHSA-q53c-4prm-w95q — shescape
Fix: ericcornelissen/shescape#2649GHSA-q53c-4prm-w95q is a CWE-116 vulnerability in shescape. A fix is available for shescape — see the affected versions and patch details below.
Shescape: Home-directory disclosure in assignment context on Unix with Dash
Exploitation Status
No confirmed exploitation observed yet
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for GHSA-q53c-4prm-w95q.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
Real-World Exposure
How broadly this vulnerability is actually deployed: weekly install volume shows current usage, and reverse-dependency count shows how many other packages break if it stays unpatched.
shescapenpmDescription
Impact
This impacts users of Shescape on Unix systems that explicitly configure shell to Dash, or true when the default shell is Dash, using the escape and escapeAll APIs in assignments prefixed to a command.
An attacker may be able to obtain the location of the home directory and, depending on how it is used, change the location on which a command operates in unexpected ways.
import * as cp from "node:child_process";
import { Shescape } from "shescape";
// 1. Prerequisites
const options = {
shell: "dash",
// Or
shell: true, // Only if the default shell is Dash
};
// 2. Payload
const payload = ":~";
// 3. Usage
const shescape = new Shescape(options);
let escapedPayload;
escapedPayload = shescape.escape(payload);
// Or
escapedPayload = shescape.escapeAll([payload]);
// And (example)
const result = cp.execSync(`V=${escapedPayload}; echo $V`, options);
// 4. Impact
console.log(result.toString());
// Outputs ":" followed by the user's home directory
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 it 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 1) refrain from using Dash, 2) use the env option of the node:child_process API to inject variables with untrusted values instead, or 3) remove all instances of ~ 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)
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | shescape | all versions | 2.1.14npm install shescape@2.1.14 |
| 📦npm | shescape | ≥ 3.0.0&&< 3.0.1 | 3.0.1npm install shescape@3.0.1 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for shescape, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update shescape to 2.1.14 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-q53c-4prm-w95q is resolved across your whole dependency graph.
Workarounds
Assume what was exposed is already known: rotate any credential, token or key that the affected component could return, restrict the endpoint to callers that genuinely need it, and strip sensitive fields from responses and error output at the boundary rather than relying on the client not to read them.
Frequently Asked Questions
Is GHSA-q53c-4prm-w95q in your dependencies?
Find it across npm, including transitive dependencies.