How severe is CVE-2024-27303?

CVE-2024-27303 has a CVSS score of 7.3/10, rated HIGH. Immediate patching is strongly recommended.

Which packages are affected by CVE-2024-27303?

CVE-2024-27303 affects the following packages: app-builder-lib (npm). Ecosystems affected: npm.

How do I fix CVE-2024-27303?

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.

How do I detect CVE-2024-27303 in my npm dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for app-builder-lib. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.

How do I mitigate CVE-2024-27303 if there is no patch (or I can't update yet)?

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 does O3 Security protect against CVE-2024-27303?

O3 pinpoints whether CVE-2024-27303 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.

Is CVE-2024-27303 actively exploited in the wild?

No public exploit code has been indexed for CVE-2024-27303 yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for CVE-2024-27303?

CVE-2024-27303 has an EPSS (Exploit Prediction Scoring System) score of 0.3%, placing it in the 20th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

What type of vulnerability is CVE-2024-27303?

CVE-2024-27303 is classified as CWE-426 (CWE-426), CWE-427 (CWE-427). These weakness types describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was CVE-2024-27303 published, and has it been updated?

CVE-2024-27303 was published on March 6, 2024 and was last updated on April 10, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

📦 npm

CVE-2024-27303

HIGH

electron-builder's NSIS installer - execute arbitrary code on the target machine (Windows only)

Also known asGHSA-r4pf-3v7r-hh55

Published

Mar 6, 2024

Updated

Apr 10, 2026

Affected

1 pkg

Patched

1 / 1

Exploits

None indexed

EPSS Exploitation Probability

via FIRST.org ↗

0.3%probability of exploitation in next 30 days

Lower Risk20th percentile+0.07%

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.

Blast Radius

1 pkg affected

Weekly download volume for affected packages — a proxy for how broadly this vulnerability is deployed.

app-builder-libnpm

3.1Mdownloads / week

Description

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

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
📦npm	`app-builder-lib`	all versions	24.13.2

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for app-builder-lib. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
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.
How O3 protects you
O3 pinpoints whether CVE-2024-27303 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.

Tailored to CVE-2024-27303. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

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 f

O3 Security · Impact-Aware SCA

Is CVE-2024-27303 in your dependencies?

O3 detects CVE-2024-27303 across npm dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.

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