CVE-2025-32033 is a high-severity (CVSS 7.5) Buffer Overflow vulnerability in apollo-router. A fix is available for apollo-router — see the affected versions and patch details below.
Apollo Router Operation Limits Vulnerable to Bypass via Integer Overflow
Exploitation Status
No confirmed exploitation observed yet
- CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2025-32033.
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.
How urgent is this, really
CVE-2025-32033 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 377,636 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
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 allowed certain queries to bypass configured operation limits, specifically due to integer overflow.
Details
The operation limits plugin uses unsigned 32-bit integers to track limit counters (e.g. for a query's height). If a counter exceeded the maximum value for this data type (4,294,967,295), it wrapped around to 0, unintentionally allowing queries to bypass configured thresholds. This could occur for large queries if the payload limit were sufficiently increased, but could also occur for small queries with deeply nested and reused named fragments.
Fix/Mitigation
Logic was updated to ensure counter overflow is handled correctly and does not wrap around to 0.
Patches
This has been remediated in apollo-router versions 1.61.2 and 2.1.1.
Workarounds
The only known workaround is "Safelisting" or "Safelisting with IDs only" per Safelisting with Persisted Queries - Apollo GraphQL Docs.
Acknowledgements
We appreciate the efforts of the security community in identifying and improving the performance and security of operation limiting mechanisms.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🦀crates.io | apollo-router | all versions | 1.61.2cargo update -p apollo-router --precise 1.61.2 |
| 🦀crates.io | apollo-router | ≥ 2.0.0-alpha.0&&< 2.1.1 | 2.1.1cargo update -p apollo-router --precise 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, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update apollo-router to 1.61.2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2025-32033 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 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2025-32033 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2025-32033. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2025-32033 in your dependencies?
O3 Security finds CVE-2025-32033 across crates.io dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.