Parse Server CVE-2026-105828

Exploitation requires the target to run Parse Server with the GraphQL API enabled and public introspection disabled - the specific mode in which validation errors still leak hidden pointer and relation target class names. The attacker must possess the deployment's public Application Id (normally embedded in client applications, so effectively public) and craft operations that provoke unknown-argument or invalid-enum-value errors. Limiting factors: deployments that do not expose the GraphQL endpoint are unaffected, and the impact is confined to disclosure of internal class names (confidentiality-low) with no write or availability consequences; no user interaction or authentication beyond the public Application Id is needed.

This is a genuine but low-to-moderate priority issue - an information-disclosure (CWE-209) weakness, not a code-execution or data-breach flaw. The vendor-supplied CVSS 4.0 vector (AV:N/AC:L/AT:P/PR:N/UI:N) with a VC:L/VI:N/VA:N impact correctly characterizes it: network-reachable, no authentication (only the public Application Id is needed), but limited to low confidentiality impact (leakage of hidden class names) with no integrity or availability effect. The AT:P flag signals an attack requirement - the deployment must have the GraphQL API enabled with public introspection disabled - which is the specific precondition for the bug to be observable. No EPSS score was provided in the input, and the CVE is not listed in CISA KEV; no public exploit code is referenced. The signals are internally consistent: a medium CVSS (6.3) with low technical impact and a present attack requirement points to a configuration-metadata leak useful mainly for reconnaissance, not a standalone high-risk vulnerability. There is no conflict between the CVSS network vector and the description, since the GraphQL endpoint is network-facing and the Application Id is public by design. Realistically this is a defense-in-depth fix that raises the floor for an attacker's enumeration efforts rather than an urgent emergency.

An attacker who has obtained a deployment's public Application Id (routinely shipped in client apps) sends crafted GraphQL operations to the Parse Server endpoint that intentionally trigger unknown-argument or invalid-enum-value validation errors. Even with public introspection turned off, the verbose error messages echo back pointer and relation target class names, letting the attacker map the hidden schema for further targeted reconnaissance. No public exploit identified at time of analysis, but the technique requires only a standard GraphQL client and no authentication.