CVE-2019-5437 is a medium-severity (CVSS 5.3) CWE-548 vulnerability in harp. 1 public exploit reference exists, so weaponization risk is real. A fix is available for harp — see the affected versions and patch details below.
Unauthorized File Access in harp
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
CVE-2019-5437 by exploitation likelihood (EPSS) against impact (CVSS). Outside the shaded patch-first corner.
Where this sits among everything scored
Of 395,249 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Counts from FIRST.org, log-scaled.
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.
harpnpmDescription
Affected versions of harp are vulnerable to Unauthorized File Access. The package states that it ignores files and directories with names that start with an underscore, such as _secret-folder. If the underscore character is URL encoded the server delivers the file.
Recommendation
Upgrade to version 0.40.2 or later.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | harp | all versions | 0.40.2npm install harp@0.40.2 |
Affected Products
harpharpjsResearch 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 harp, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update harp to 0.40.2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2019-5437 is resolved across your whole dependency graph.
Workarounds
Assume what was exposed is already known: rotate any credential, token or key that the affected component could return, restrict the endpoint to callers that genuinely need it, and strip sensitive fields from responses and error output at the boundary rather than relying on the client not to read them.
Frequently Asked Questions
Is CVE-2019-5437 in your dependencies?
Find it across npm, including transitive dependencies.