Add MaxSelectionSetSize option to prevent DDoS attacks#10
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Fixes a critical DDoS vulnerability where queries with thousands of
fields at the same level cause CPU overload due to O(n²) validation
complexity.
Changes:
- Add MaxSelectionSetSize configuration option (default: 0/disabled)
- Validate selection set size before expensive overlap checks
- Reject malicious queries in ~1ms vs 30+ second timeout
- Add comprehensive test suite for vulnerability and fix
- Add GitHub Actions workflow for CI/CD
The fix is backward compatible and opt-in. Recommended values: 100-1000
depending on schema complexity.
Example usage:
schema := graphql.MustParseSchema(schemaString, resolver,
graphql.MaxSelectionSetSize(100))
Signed-off-by: peterdeme <[email protected]>
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WSpacelifT
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Oct 15, 2025
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Fixes a critical DDoS vulnerability where queries with thousands of
fields at the same level cause CPU overload due to O(n²) validation
complexity.
Changes:
The fix is backward compatible and opt-in. Recommended values: 100-1000
depending on schema complexity.
Example usage:
schema := graphql.MustParseSchema(schemaString, resolver, graphql.MaxSelectionSetSize(100))