GHSA-9jxc-qjr9-vjxq
HIGHelectron-updater Code Signing Bypass on Windows
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.
Blast Radius
Weekly download volume for affected packages — a proxy for how broadly this vulnerability is deployed.
electron-updaternpmDescription
Observations
The file packages/electron-updater/src/windowsExecutableCodeSignatureVerifier.ts implements the signature validation routine for Electron applications on Windows. It executes the following command in a new shell (process.env.ComSpec on Windows, usually C:\Windows\System32\cmd.exe):
Because of the surrounding shell, a first pass by cmd.exe expands any environment variable found in command-line above.
Exploitation
This creates a situation where verifySignature() can be tricked into validating the certificate of a different file than the one that was just downloaded. If the step is successful, the malicious update will be executed even if its signature is invalid.
Impact
This attack assumes a compromised update manifest (server compromise, Man-in-the-Middle attack if fetched over HTTP, Cross-Site Scripting to point the application to a malicious updater server, etc.).
Patch
This vulnerability was patched in #8295, by comparing the path in the output of Get-AuthenticodeSignature with the intended one. The patch is available starting from 6.3.0-alpha.6.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | electron-updater | all versions | 6.3.0-alpha.6 |
Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for electron-updater. 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 electron-updater to 6.3.0-alpha.6 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-9jxc-qjr9-vjxq 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 GHSA-9jxc-qjr9-vjxq 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 GHSA-9jxc-qjr9-vjxq. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is GHSA-9jxc-qjr9-vjxq in your dependencies?
O3 detects GHSA-9jxc-qjr9-vjxq across npm dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.