CVE-2025-32030: Apollo Gateway DOS Vulnerability

CVE-2025-32030 Overview

A denial of service vulnerability exists in Apollo Gateway, a utility for combining multiple GraphQL microservices into a single GraphQL endpoint. Prior to version 2.10.1, the query planning mechanism improperly handled deeply nested and reused named fragments, leading to exponential resource usage during fragment expansion. This algorithmic complexity attack allows unauthenticated remote attackers to cause excessive resource consumption and denial of service by crafting malicious GraphQL queries.

Critical Impact

Unauthenticated attackers can exploit this vulnerability remotely to cause denial of service through resource exhaustion, potentially rendering GraphQL-based applications and APIs completely unavailable.

Affected Products

• Apollo Gateway versions prior to 2.10.1
• @apollo/gateway npm package (Node.js)
• GraphQL federated microservices using vulnerable Apollo Gateway versions

Discovery Timeline

• 2025-04-07 - CVE-2025-32030 published to NVD
• 2025-08-01 - Last updated in NVD database

Technical Details for CVE-2025-32030

Vulnerability Analysis

This vulnerability is classified under CWE-770 (Allocation of Resources Without Limits or Throttling). The flaw resides in Apollo Gateway's query planning logic, specifically in how named fragments are processed and expanded during query execution planning.

When Apollo Gateway receives a GraphQL query containing named fragments, it expands these fragments to understand the complete query structure for planning purposes. The vulnerable implementation expanded named fragments once per fragment spread encountered during query planning. When an attacker crafts a query with deeply nested fragments that reference each other repeatedly, the expansion process follows an exponential growth pattern.

For example, if a fragment references itself through nested structures multiple times, each level of nesting multiplies the expansion work required. This creates an algorithmic complexity vulnerability where relatively small malicious queries can trigger massive computational overhead, exhausting server CPU and memory resources.

Root Cause

The root cause stems from the naive implementation of named fragment expansion in the query planner. Rather than caching or memoizing fragment expansions, the system performed redundant expansions for each fragment spread reference. This design flaw transforms what should be linear or polynomial time complexity into exponential time complexity when processing queries with deeply nested, reused fragment structures.

Attack Vector

The attack vector is network-based and requires no authentication or user interaction. An attacker can exploit this vulnerability by sending specially crafted GraphQL queries to any exposed Apollo Gateway endpoint. The attack leverages the following characteristics:

The attacker constructs a GraphQL query containing multiple named fragments with deep nesting and cross-references between fragments. When the gateway's query planner processes this malicious query, each fragment spread triggers a full expansion of the referenced fragment, including all its nested fragment spreads. This recursive expansion without proper bounds checking leads to exponential resource consumption.

The attack is particularly effective because GraphQL endpoints are typically designed to handle complex queries, making it difficult to distinguish between legitimate complex queries and malicious ones without specific protections against this vulnerability pattern.

Detection Methods for CVE-2025-32030

Indicators of Compromise

• Abnormal CPU or memory spikes on servers running Apollo Gateway
• GraphQL queries containing unusually deep fragment nesting patterns
• Slow or unresponsive GraphQL API endpoints without proportional traffic increases
• Server logs showing query planning timeouts or memory allocation failures

Detection Strategies

• Implement query complexity analysis to identify and flag queries with excessive fragment depth or reuse patterns
• Monitor resource utilization metrics (CPU, memory) on Apollo Gateway instances for anomalous spikes
• Deploy Web Application Firewall (WAF) rules to detect and block GraphQL queries with suspicious fragment patterns
• Enable detailed logging of query planning duration to identify abnormally slow query processing

Monitoring Recommendations

• Set up alerts for query planning operations exceeding normal duration thresholds
• Monitor the ratio of query complexity to response time for anomaly detection
• Implement rate limiting on GraphQL endpoints to mitigate the impact of exploitation attempts
• Track memory allocation patterns during query processing for early detection of resource exhaustion attacks

How to Mitigate CVE-2025-32030

Immediate Actions Required

• Upgrade @apollo/gateway to version 2.10.1 or later immediately
• Implement query depth limiting on GraphQL endpoints as a defense-in-depth measure
• Enable query cost analysis to reject excessively complex queries before planning
• Review and audit exposed GraphQL endpoints for proper access controls and rate limiting

Patch Information

Apollo has released @apollo/gateway version 2.10.1 which remediates this vulnerability by optimizing the named fragment expansion logic during query planning. The fix prevents the exponential resource usage by implementing proper caching and bounds checking for fragment expansions.

For detailed information about the fix, refer to the GitHub Pull Request #3236 and the GitHub Security Advisory GHSA-q2f9-x4p4-7xmh. The patched version is available at the GitHub Release Tag.

Workarounds

• Implement query complexity limits using GraphQL depth limiting middleware before queries reach the gateway
• Deploy a reverse proxy or WAF with rules to reject queries exceeding reasonable fragment nesting thresholds
• Implement request timeout mechanisms to terminate long-running query planning operations
• Consider temporary rate limiting on GraphQL endpoints while planning the upgrade

# Upgrade Apollo Gateway to patched version
npm update @apollo/gateway@2.10.1

# Verify installed version
npm list @apollo/gateway