CVE-2024-27303 is a high-severity (CVSS 7.3) CWE-426 vulnerability in app-builder-lib. A fix is available for app-builder-lib — see the affected versions and patch details below.
electron-builder's NSIS installer - execute arbitrary code on the target machine (Windows only)
Exploitation Status
No confirmed exploitation observed yet
- A successful exploit gives an attacker total control of the affected component, not partial access.
- 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-2024-27303.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
Where this sits among everything scored
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.
app-builder-libnpmDescription
electron-builder is a solution to package and build a ready for distribution Electron, Proton Native app for macOS, Windows and Linux. A vulnerability that only affects eletron-builder prior to 24.13.2 in Windows, the NSIS installer makes a system call to open cmd.exe via NSExec in the .nsh installer script. NSExec by default searches the current directory of where the installer is located before searching PATH. This means that if an attacker can place a malicious executable file named cmd.exe in the same folder as the installer, the installer will run the malicious file. Version 24.13.2 fixes this issue. No known workaround exists. The code executes at the installer-level before the app is present on the system, so there's no way to check if it exists in a current installer.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | app-builder-lib | all versions | 24.13.2npm install app-builder-lib@24.13.2 |
Affected Products
electron-builderelectronDetection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for app-builder-lib, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update app-builder-lib to 24.13.2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2024-27303 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.
Frequently Asked Questions
Is CVE-2024-27303 in your dependencies?
Find it across npm, including transitive dependencies.