fix: GraphQL error messages disclose pointer and relation target class names when public introspection is disabled ([GHSA-r2g6-4f6j-f6rf](https://github.com/parse-community/parse-server/security/advisories/GHSA-r2g6-4f6j-f6rf)) (#10569)

spec/ParseGraphQLServer.spec.js

@@ -1056,6 +1056,377 @@ describe('ParseGraphQLServer', () => {
             expect(JSON.stringify(error)).not.toContain('secretRequiredField');
           }
         });
+
+        // A Pointer/Relation field maps to a generated input type whose name embeds the
+        // pointer's TARGET class (`<Target>PointerInput`, `<Target>RelationWhereInput`,
+        // `Create<Target>FieldsInput`). graphql-js interpolates that type name into base
+        // coercion/validation messages that the "Did you mean" and required-field strips do
+        // not touch, disclosing the target class name to a caller who only supplied the
+        // pointer field name (which does not reveal its target). Redact those identifiers
+        // for callers that are not allowed to introspect.
+        const setupPointerSchema = async _parseServer => {
+          const schemaController = await _parseServer.config.databaseController.loadSchema();
+          await schemaController.addClassIfNotExists('SecretAuthor', {
+            name: { type: 'String' },
+          });
+          await schemaController.addClassIfNotExists('DiagBook', {
+            writtenBy: { type: 'Pointer', targetClass: 'SecretAuthor' },
+          });
+          await resetGraphQLCache();
+        };
+
+        it('should strip pointer target class names from where-clause validation errors without master or maintenance key', async () => {
+          await setupPointerSchema(parseServer);
+
+          try {
+            await apolloClient.query({
+              query: gql`
+                query Leak {
+                  diagBooks(where: { writtenBy: 123 }) {
+                    edges {
+                      node {
+                        id
+                      }
+                    }
+                  }
+                }
+              `,
+            });
+            fail('should have thrown a validation error');
+          } catch (e) {
+            const error = getReturnedError(e);
+            // Expected value of type "SecretAuthorRelationWhereInput", found 123.
+            expect(error.message).not.toContain('SecretAuthor');
+            expect(JSON.stringify(error)).not.toContain('SecretAuthor');
+          }
+        });
+
+        it('should strip pointer target class names from non-object variable-coercion errors without master or maintenance key', async () => {
+          await setupPointerSchema(parseServer);
+
+          try {
+            await apolloClient.mutate({
+              mutation: gql`
+                mutation Create($input: CreateDiagBookInput!) {
+                  createDiagBook(input: $input) {
+                    diagBook {
+                      id
+                    }
+                  }
+                }
+              `,
+              variables: { input: { fields: { writtenBy: { createAndLink: 5 } } } },
+            });
+            fail('should have thrown a coercion error');
+          } catch (e) {
+            const error = getReturnedError(e);
+            // Expected type "CreateSecretAuthorFieldsInput" to be an object.
+            expect(error.message).not.toContain('SecretAuthor');
+            expect(JSON.stringify(error)).not.toContain('SecretAuthor');
+          }
+        });
+
+        it('should strip pointer target class names from unknown-field variable-coercion errors without master or maintenance key', async () => {
+          await setupPointerSchema(parseServer);
+
+          try {
+            await apolloClient.mutate({
+              mutation: gql`
+                mutation Create($input: CreateDiagBookInput!) {
+                  createDiagBook(input: $input) {
+                    diagBook {
+                      id
+                    }
+                  }
+                }
+              `,
+              variables: { input: { fields: { writtenBy: { bogusKey: 1 } } } },
+            });
+            fail('should have thrown a coercion error');
+          } catch (e) {
+            const error = getReturnedError(e);
+            // Field "bogusKey" is not defined by type "SecretAuthorPointerInput".
+            expect(error.message).not.toContain('SecretAuthor');
+            expect(JSON.stringify(error)).not.toContain('SecretAuthor');
+          }
+        });
+
+        it('should keep pointer target class names in errors with master key', async () => {
+          await setupPointerSchema(parseServer);
+
+          try {
+            await apolloClient.query({
+              query: gql`
+                query Leak {
+                  diagBooks(where: { writtenBy: 123 }) {
+                    edges {
+                      node {
+                        id
+                      }
+                    }
+                  }
+                }
+              `,
+              context: {
+                headers: {
+                  'X-Parse-Master-Key': 'test',
+                },
+              },
+            });
+            fail('should have thrown a validation error');
+          } catch (e) {
+            const error = getReturnedError(e);
+            expect(error.message).toContain('SecretAuthor');
+          }
+        });
+
+        it('should keep pointer target class names in errors when public introspection is enabled', async () => {
+          const parseServer = await reconfigureServer();
+          await createGQLFromParseServer(parseServer, { graphQLPublicIntrospection: true });
+          await setupPointerSchema(parseServer);
+
+          try {
+            await apolloClient.query({
+              query: gql`
+                query Leak {
+                  diagBooks(where: { writtenBy: 123 }) {
+                    edges {
+                      node {
+                        id
+                      }
+                    }
+                  }
+                }
+              `,
+            });
+            fail('should have thrown a validation error');
+          } catch (e) {
+            const error = getReturnedError(e);
+            expect(error.message).toContain('SecretAuthor');
+          }
+        });
+
+        it('should strip pointer target class names from non-nullable variable-coercion errors without master or maintenance key', async () => {
+          const schemaController = await parseServer.config.databaseController.loadSchema();
+          await schemaController.addClassIfNotExists('SecretAuthor', { name: { type: 'String' } });
+          await schemaController.addClassIfNotExists('ReqDiagBook', {
+            writtenBy: { type: 'Pointer', targetClass: 'SecretAuthor', required: true },
+          });
+          await resetGraphQLCache();
+
+          try {
+            await apolloClient.mutate({
+              mutation: gql`
+                mutation Create($input: CreateReqDiagBookInput!) {
+                  createReqDiagBook(input: $input) {
+                    reqDiagBook {
+                      id
+                    }
+                  }
+                }
+              `,
+              variables: { input: { fields: { writtenBy: null } } },
+            });
+            fail('should have thrown a coercion error');
+          } catch (e) {
+            const error = getReturnedError(e);
+            // Expected non-nullable type "SecretAuthorPointerInput!" not to be null.
+            expect(error.message).not.toContain('SecretAuthor');
+            expect(JSON.stringify(error)).not.toContain('SecretAuthor');
+          }
+        });
+
+        it('should strip pointer target class names from variable-position validation errors without master or maintenance key', async () => {
+          await setupPointerSchema(parseServer);
+
+          try {
+            await apolloClient.query({
+              query: gql`
+                query Leak($x: String) {
+                  diagBooks(where: { writtenBy: $x }) {
+                    edges {
+                      node {
+                        id
+                      }
+                    }
+                  }
+                }
+              `,
+              variables: { x: 'anything' },
+            });
+            fail('should have thrown a validation error');
+          } catch (e) {
+            const error = getReturnedError(e);
+            // Variable "$x" of type "String" used in position expecting type "SecretAuthorRelationWhereInput".
+            expect(error.message).not.toContain('SecretAuthor');
+            expect(JSON.stringify(error)).not.toContain('SecretAuthor');
+          }
+        });
+
+        it('should strip pointer target class names from mutation variable-position validation errors without master or maintenance key', async () => {
+          await setupPointerSchema(parseServer);
+
+          try {
+            await apolloClient.mutate({
+              mutation: gql`
+                mutation Create($x: String) {
+                  createDiagBook(input: { fields: { writtenBy: { createAndLink: $x } } }) {
+                    diagBook {
+                      id
+                    }
+                  }
+                }
+              `,
+              variables: { x: 'anything' },
+            });
+            fail('should have thrown a validation error');
+          } catch (e) {
+            const error = getReturnedError(e);
+            // Variable "$x" of type "String" used in position expecting type "CreateSecretAuthorFieldsInput".
+            expect(error.message).not.toContain('SecretAuthor');
+            expect(JSON.stringify(error)).not.toContain('SecretAuthor');
+          }
+        });
+
+        it('should strip pointer target class names from output-field validation errors without master or maintenance key', async () => {
+          await setupPointerSchema(parseServer);
+
+          try {
+            await apolloClient.query({
+              query: gql`
+                query Leak {
+                  diagBooks(where: {}) {
+                    edges {
+                      node {
+                        writtenBy {
+                          bogusSubField
+                        }
+                      }
+                    }
+                  }
+                }
+              `,
+            });
+            fail('should have thrown a validation error');
+          } catch (e) {
+            const error = getReturnedError(e);
+            // Cannot query field "bogusSubField" on type "SecretAuthor".
+            expect(error.message).not.toContain('SecretAuthor');
+            expect(JSON.stringify(error)).not.toContain('SecretAuthor');
+          }
+        });
+
+        it('should strip pointer target class names from scalar-leaf validation errors without master or maintenance key', async () => {
+          await setupPointerSchema(parseServer);
+
+          try {
+            await apolloClient.query({
+              query: gql`
+                query Leak {
+                  diagBooks(where: {}) {
+                    edges {
+                      node {
+                        writtenBy
+                      }
+                    }
+                  }
+                }
+              `,
+            });
+            fail('should have thrown a validation error');
+          } catch (e) {
+            const error = getReturnedError(e);
+            // Field "writtenBy" of type "SecretAuthor" must have a selection of subfields.
+            expect(error.message).not.toContain('SecretAuthor');
+            expect(JSON.stringify(error)).not.toContain('SecretAuthor');
+          }
+        });
+
+        it('should keep pointer target class names in output-field errors with master key', async () => {
+          await setupPointerSchema(parseServer);
+
+          try {
+            await apolloClient.query({
+              query: gql`
+                query Leak {
+                  diagBooks(where: {}) {
+                    edges {
+                      node {
+                        writtenBy
+                      }
+                    }
+                  }
+                }
+              `,
+              context: {
+                headers: {
+                  'X-Parse-Master-Key': 'test',
+                },
+              },
+            });
+            fail('should have thrown a validation error');
+          } catch (e) {
+            const error = getReturnedError(e);
+            expect(error.message).toContain('SecretAuthor');
+          }
+        });
+
+        it('should strip pointer target class names from fragment-spread validation errors without master or maintenance key', async () => {
+          await setupPointerSchema(parseServer);
+
+          try {
+            await apolloClient.query({
+              query: gql`
+                query Leak {
+                  diagBooks(where: {}) {
+                    edges {
+                      node {
+                        writtenBy {
+                          ... on DiagBook {
+                            id
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+              `,
+            });
+            fail('should have thrown a validation error');
+          } catch (e) {
+            const error = getReturnedError(e);
+            // Fragment cannot be spread here as objects of type "SecretAuthor" can never be of type "DiagBook".
+            expect(error.message).not.toContain('SecretAuthor');
+            expect(JSON.stringify(error)).not.toContain('SecretAuthor');
+          }
+        });
+
+        it('should keep caller-referenced input type names in validation errors without master or maintenance key', async () => {
+          await setupPointerSchema(parseServer);
+
+          try {
+            await apolloClient.query({
+              query: gql`
+                query Leak($where: DiagBookWhereInput) {
+                  diagBooks(where: $where) {
+                    edges {
+                      node {
+                        id
+                      }
+                    }
+                  }
+                }
+              `,
+              variables: { where: { nonexistentField: { equalTo: 1 } } },
+            });
+            fail('should have thrown a validation error');
+          } catch (e) {
+            const error = getReturnedError(e);
+            // The caller referenced DiagBookWhereInput in the operation text, so it is not a
+            // schema disclosure and must be preserved to keep validation feedback useful.
+            expect(error.message).toContain('DiagBookWhereInput');
+          }
+        });
       });
 
 

src/GraphQL/ParseGraphQLServer.js

@@ -82,8 +82,82 @@ const stripSchemaCoercionIdentifiers = message =>
     )
     : message;
 
-const stripSchemaIdentifiers = message =>
+// graphql-js also emits base coercion / validation messages that name a nested input
-  stripSchemaCoercionIdentifiers(stripSchemaSuggestion(message));
+// TYPE without a "Did you mean" clause, so neither strip above reaches them. For a
+// Pointer or Relation field the generated input type name embeds the pointer's TARGET
+// class (`<Target>PointerInput`, `<Target>RelationWhereInput`, `Create<Target>FieldsInput`)
+// — a class the caller never referenced and cannot derive from the field name they
+// supplied — so these templates disclose a schema class name to a caller who has only the
+// public application id. Redact the quoted type identifier from those templates UNLESS the
+// caller referenced it in the operation text: a type name the caller wrote in the operation
+// (e.g. `$where: UserWhereInput`) is not a disclosure, and preserving it keeps the message
+// ('... is not defined by type "UserWhereInput".') useful. When the operation text is
+// unavailable the identifier is redacted (fail closed).
+const stripSchemaTypeIdentifiers = (message, operationText) => {
+  if (typeof message !== 'string') { return message; }
+  // A generated type identifier counts as "referenced" (and therefore not a disclosure) only if
+  // the caller wrote it as a whole token in the operation text. Tokenize the operation on
+  // non-identifier characters and compare exact tokens rather than building a RegExp from the
+  // captured name: this avoids substring false-matches (e.g. preserving "AuthorPointerInput"
+  // because the operation contains "SecretAuthorPointerInput") and any regex injection/ReDoS from
+  // an unusual captured name. GraphQL list/non-null wrappers ("[", "]", "!") are stripped from the
+  // captured name so e.g. "SecretAuthorPointerInput!" still matches "$x: SecretAuthorPointerInput!".
+  // When the operation text is unavailable the type is treated as not referenced (fail closed).
+  const referencedTokens =
+    typeof operationText === 'string'
+      ? new Set(operationText.split(/[^_A-Za-z0-9]+/).filter(Boolean))
+      : new Set();
+  const isReferenced = typeName => referencedTokens.has(typeName.replace(/[[\]!]/g, ''));
+  return message
+    // Input coercion / ValuesOfCorrectTypeRule (variables and inline literals).
+    .replace(/Expected value of type "([^"]+)"/g, (match, typeName) =>
+      isReferenced(typeName) ? match : 'Expected value of the correct type'
+    )
+    .replace(/Expected type "([^"]+)" to be an object\./g, (match, typeName) =>
+      isReferenced(typeName) ? match : 'Expected an object.'
+    )
+    .replace(/Expected non-nullable type "([^"]+)" not to be null\./g, (match, typeName) =>
+      isReferenced(typeName) ? match : 'Expected a non-null value.'
+    )
+    .replace(/ is not defined by type "([^"]+)"\./g, (match, typeName) =>
+      isReferenced(typeName) ? match : ' is not defined.'
+    )
+    // VariablesInAllowedPositionRule: the position type is the pointer/relation target
+    // input type; the caller only wrote their own variable's declared type.
+    .replace(/ used in position expecting type "([^"]+)"\./g, (match, typeName) =>
+      isReferenced(typeName) ? match : ' used in position expecting a different type.'
+    )
+    // FieldsOnCorrectTypeRule: descending into a Pointer/Relation output field names its
+    // target output object type.
+    .replace(/Cannot query field ("[^"]*") on type "([^"]+)"\./g, (match, fieldName, typeName) =>
+      isReferenced(typeName) ? match : `Cannot query field ${fieldName}.`
+    )
+    // ScalarLeafsRule: selecting a Pointer/Relation output field with no sub-selection names
+    // its target output object type.
+    .replace(
+      /Field ("[^"]*") of type "([^"]+)" must have a selection of subfields\./g,
+      (match, fieldName, typeName) =>
+        isReferenced(typeName) ? match : `Field ${fieldName} must have a selection of subfields.`
+    )
+    // PossibleFragmentSpreadsRule: an inline/named fragment on an incompatible type inside a
+    // Pointer/Relation output field names the target output object type (the parent type).
+    // Redact each type token the caller did not reference; when both are referenced the
+    // reconstruction is identical to the original message.
+    .replace(
+      /objects of type "([^"]+)" can never be of type "([^"]+)"\./g,
+      (match, parentType, fragType) => {
+        const parent = isReferenced(parentType) ? `type "${parentType}"` : 'the parent type';
+        const frag = isReferenced(fragType) ? `type "${fragType}"` : 'the given type';
+        return `objects of ${parent} can never be of ${frag}.`;
+      }
+    );
+};
+
+const stripSchemaIdentifiers = (message, operationText) =>
+  stripSchemaTypeIdentifiers(
+    stripSchemaCoercionIdentifiers(stripSchemaSuggestion(message)),
+    operationText
+  );
 
 const SchemaSuggestionsControlPlugin = (publicIntrospection) => ({
   requestDidStart: async (requestContext) => ({
@@ -104,10 +178,13 @@ const SchemaSuggestionsControlPlugin = (publicIntrospection) => ({
           : body?.kind === 'incremental'
             ? body.initialResult.errors
             : undefined;
+      const operationText = requestContext.request?.query;
       errors?.forEach(error => {
-        error.message = stripSchemaIdentifiers(error.message);
+        error.message = stripSchemaIdentifiers(error.message, operationText);
         if (Array.isArray(error.extensions?.stacktrace)) {
-          error.extensions.stacktrace = error.extensions.stacktrace.map(stripSchemaIdentifiers);
+          error.extensions.stacktrace = error.extensions.stacktrace.map(message =>
+            stripSchemaIdentifiers(message, operationText)
+          );
         }
       });
     },