nl.nl-portal:app has GraphiQL UI and GraphQL schema introspection enabled by default

published 2026-09-11 58 d ago modified 2026-09-30 39 d ago also EUVD-2026-76686

cvss: 5.3; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.4%; EPSS 0.4% chance of exploitation in 30 days, percentile 34%
public exploits: 0; none known

NL Portal Backend Libraries provide backend components for Dutch government portals that interact with residents, customers, suppliers, and partner organizations. In versions up to and including 3.0.0, deployments using the shipped default configuration exposed two GraphQL developer features without requiring authentication: the GraphiQL playground, an interactive UI for issuing GraphQL queries; and schema introspection, which lets a caller download the full description of every query, mutation, type, and argument the API supports. Anyone who could reach the `/graphiql` endpoint could open the playground in a browser, pull the full schema, and use that to map out the API and craft calls against it. By itself this does not leak user data, but it removes the guesswork from attacking the rest of the API and significantly lowers the bar for finding and exploiting other weaknesses. Version 3.0.1 patches the issue. As a workaround, override the two settings in deployed configuration.

Patch / fix

links 1

github.com/nl-portal/nl-portal-backend-libraries@0d2af76 commit

CISA SSVC

Exploitation: none
Automatable: yes
Technical impact: partial
Assessed: 55 d ago (2026-09-14)

Exploit prediction

0.40% chance of exploitation in the next 30 days, higher than 34% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CNA	3.1	5.3	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

Affected products

nl-portal nl.nl-portal:app

Classification

Weakness

CWE-200 Exposure of Sensitive Information to an Unauthorized Actor
CWE-1188 Initialization of a Resource with an Insecure Default

References

Sources

CVE List CVE-2026-49462
NVD CVE-2026-49462

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary