CVE-2026-78693: Incomplete redaction re-attaches the original error path in AshGraphql, leaking internal field names

Severity: medium (CVSS 6.9 v4.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.5% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-08-30 · updated 2026-09-01
Weakness: CWE-209

Description

Generation of Error Message Containing Sensitive Information vulnerability in ash-project ash_graphql allows a remote client to read internal field names that an application configured its error_handler to redact. In AshGraphql.Errors, each error is passed to the configured error_handler and the returned map is merged with the pre-handler path via Map.put_new(handled, :path, path). Because put_new defers to the handler only when the handler itself set :path, a sanitizing handler that returns a fresh map or deletes :path has that decision reverted. The re-injected path comes from build_error_path/5, which falls back to raw internal Ash attribute and argument names when no field_names mapping is configured. A validation failure on a non-exposed or nested field therefore returns internal names in the GraphQL error path, defeating the application's redaction. This issue affects ash_graphql: from 1.9.0 before 1.11.0.

Affected products

ash-project ash_graphql: from 1.9.0 before 1.11.0 — fixed in 1.11.0

How to fix

Upgrade to a fixed version: ash-project ash_graphql 1.11.0. Check the vendor advisory for mitigations.

References

Get alerted when CVE-2026-78693 or the next vulnerability affects your stack