CVE-2025-24959 — zx
Fix: google/zx#1094CVE-2025-24959 is a Code Injection vulnerability in zx. A fix is available for zx — see the affected versions and patch details below.
Environment Variable Injection for dotenv API in zx
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 CVE-2025-24959.
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
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.
zxnpmDescription
zx is a tool for writing better scripts. An attacker with control over environment variable values can inject unintended environment variables into process.env. This can lead to arbitrary command execution or unexpected behavior in applications that rely on environment variables for security-sensitive operations. Applications that process untrusted input and pass it through dotenv.stringify are particularly vulnerable. This issue has been patched in version 8.3.2. Users should immediately upgrade to this version to mitigate the vulnerability. If upgrading is not feasible, users can mitigate the vulnerability by sanitizing user-controlled environment variable values before passing them to dotenv.stringify. Specifically, avoid using ", ', and backticks in values, or enforce strict validation of environment variables before usage.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | zx | ≥ 8.3.1&&< 8.3.2 | 8.3.2npm install zx@8.3.2 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for zx, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update zx to 8.3.2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2025-24959 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2025-24959 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2025-24959. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2025-24959 in your dependencies?
O3 Security finds CVE-2025-24959 across npm dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.