Dgraph: Pre-Auth Full Database Exfiltration via DQL Injection in NQuad Lang Field
Date: 2026-04
Affected: go/github.com/dgraph-io/dgraph, go/github.com/dgraph-io/dgraph/v24, go/github.com/dgraph-io/dgraph/v25
Attack vector: auth-bypass
Category: vulnerability-disclosure
Severity: Critical
CVE: CVE-2026-41328
CWE: CWE-943
CVSS: 9.1 (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N)

## 1. Executive Summary A vulnerability has been found in Dgraph that gives an unauthenticated attacker full read access to every piece of data in the database. This affects Dgraph's default configuration where ACL is not enabled. The attack requires two HTTP POSTs to port 8080. The first sets up a schema predicate with `@unique @index(exact) @lang` via `/alter` (also unauthenticated in default config). The second sends a crafted JSON mutation to `/mutate?commitNow=true` where a JSON key contains the predicate name followed by `@` and a DQL injection payload in the language tag position. The injection exploits the `addQueryIfUnique` function in `edgraph/server.go`, which constructs DQL queries using `fmt.Sprintf` with unsanitized `predicateName` that includes the raw `pred.Lang` value. The `Lang` field is extracted from JSON mutation keys by `x.PredicateLang()`, which splits on `@`, and is never validated by any function in the codebase. The attacker injects a closing parenthesis to escape the `eq()` function, adds an arbitrary named query block, and uses a `#` comment to neutralize trailing template syntax. The injected query executes server-side and its results are returned in the HTTP response. POC clip: https://github.com/user-attachments/assets/bbfb7bba-c957-4b57-b534-48a958314186 ## 2. CVSS Score **CVSS 3.1: 9.1 (Critical)** ``` CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N ``` | Metric | Value | Rationale


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