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
pkgReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects npm packages — download data is not available via public APIs for these ecosystems.
Description
Impact
Any native code packages built by pkg are written to a hardcoded directory. On unix systems, this is /tmp/pkg/* which is a shared directory for all users on the same local system. There is no uniqueness to the package names within this directory, they are predictable.
An attacker who has access to the same local system has the ability to replace the genuine executables in the shared directory with malicious executables of the same name. A user may then run the malicious executable without realising it has been modified.
Patches
This package is deprecated. Therefore, there will not be a patch provided for this vulnerability.
Recommended Action:
To check if your executable build by pkg depends on native code and is vulnerable, run the executable and check if /tmp/pkg/ was created.
Users should transition to actively maintained alternatives. We would recommend investigating Node.js 21’s support for single executable applications.
Workarounds
Given the decision to deprecate the pkg package, there are no official workarounds or remediations provided by our team. Users should prioritize migrating to other packages that offer similar functionality with enhanced security.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | pkg | all versions | No fix |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for pkg. 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.
Remediation status
No patched version of pkg has shipped for GHSA-22r3-9w55-cj54 yet. Where your build allows, override or pin the dependency away from the vulnerable range, and apply any maintainer-recommended mitigation.
Mitigate without a patch
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-22r3-9w55-cj54 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-22r3-9w55-cj54. 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-22r3-9w55-cj54 in your dependencies?
O3 detects GHSA-22r3-9w55-cj54 across npm dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.