GHSA-3j43-9v8v-cp3f
HIGHApollo Router Query Validation Vulnerable to Excessive Resource Consumption via Named Fragment Processing
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
Blast Radius
apollo-router🦀apollo-routerReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects crates.io packages — download data is not available via public APIs for these ecosystems.
Description
Impact
Summary
A vulnerability in Apollo Router's usage of Apollo Compiler allowed queries with deeply nested and reused named fragments to be prohibitively expensive to validate. This could lead to excessive resource consumption and denial of service.
Details
Named fragments were being processed once per fragment spread in some cases during query validation, leading to exponential resource usage when deeply nested and reused fragments were involved.
Fix/Mitigation
Apollo Router's usage of Apollo Compiler has been updated so that validation logic processes each named fragment only once, preventing redundant traversal.
Patches
This has been remediated in apollo-router versions 1.61.2 and 2.1.1.
Workarounds
The only known workaround is "Safelisting with IDs only" per Safelisting with Persisted Queries - Apollo GraphQL Docs. The "Safelisting" security level is not sufficient, since that level allows freeform GraphQL queries to be sent to Apollo Router.
References
Acknowledgements
We appreciate the efforts of the security community in identifying and improving the performance and security of query validation mechanisms.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🦀crates.io | apollo-router | all versions | 1.61.2 |
| 🦀crates.io | apollo-router | ≥ 2.0.0-alpha.0&&< 2.1.1 | 2.1.1 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for apollo-router. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update apollo-router to 1.61.2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-3j43-9v8v-cp3f is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether GHSA-3j43-9v8v-cp3f is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to GHSA-3j43-9v8v-cp3f. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is GHSA-3j43-9v8v-cp3f in your dependencies?
O3 detects GHSA-3j43-9v8v-cp3f across crates.io dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.