CVE-2019-19507 — jpv
MEDIUMCVE-2019-19507 is a medium-severity (CVSS 5.3) Improper Authentication vulnerability in jpv. 1 public exploit reference exists, so weaponization risk is real. A fix is available for jpv — see the affected versions and patch details below.
Validation bypass is possible in Json Pattern Validator
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
CVE-2019-19507 by exploitation likelihood (EPSS) against impact (CVSS). Outside the shaded patch-first corner.
Where this sits among everything scored
Of 385,738 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.
jpvnpmDescription
In jpv (aka Json Pattern Validator) before 2.1.1, compareCommon() can be bypassed because certain internal attributes can be overwritten via a conflicting name, as demonstrated by 'constructor': {'name':'Array'}. This affects validate(). Hence, a crafted payload can overwrite this builtin attribute to manipulate the type detection result.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | jpv | all versions | 2.1.1npm install jpv@2.1.1 |
Affected Products
json pattern validatorjson_pattern_validator_projectResearch 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 jpv, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update jpv to 2.1.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2019-19507 is resolved across your whole dependency graph.
Workarounds
Put an independent control in front of the weakness: restrict the affected endpoint or interface to trusted networks, require an additional authentication factor or proxy-level check, and invalidate existing sessions and credentials in case the flaw has already been used.
Frequently Asked Questions
Is CVE-2019-19507 in your dependencies?
Find it across npm, including transitive dependencies.