How severe is CVE-2026-32621?

CVE-2026-32621 has a CVSS score of 9.9/10, rated CRITICAL. Immediate patching is strongly recommended.

Which packages are affected by CVE-2026-32621?

CVE-2026-32621 affects the following packages: @apollo/federation-internals (npm), @apollo/federation-internals (npm), @apollo/federation-internals (npm), @apollo/federation-internals (npm), @apollo/federation-internals (npm), @apollo/gateway (npm), @apollo/gateway (npm), @apollo/gateway (npm), and 7 more. Ecosystems affected: npm.

How do I fix CVE-2026-32621?

Update @apollo/federation-internals to 2.9.6 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-32621 is resolved across your whole dependency graph.

How do I detect CVE-2026-32621 in my npm dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for @apollo/federation-internals. 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.

How do I mitigate CVE-2026-32621 if there is no patch (or I can't update yet)?

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 does O3 Security protect against CVE-2026-32621?

O3 pinpoints whether CVE-2026-32621 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.

Is CVE-2026-32621 actively exploited in the wild?

No public exploit code has been indexed for CVE-2026-32621 yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for CVE-2026-32621?

CVE-2026-32621 has an EPSS (Exploit Prediction Scoring System) score of 0.5%, placing it in the 40th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

What type of vulnerability is CVE-2026-32621?

CVE-2026-32621 is classified as CWE-1321 (CWE-1321). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was CVE-2026-32621 published, and has it been updated?

CVE-2026-32621 was published on March 13, 2026 and was last updated on April 10, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

CVE-2026-32621: @apollo/federation-intern… (Critical 9.9)

EPSS Exploitation Probability

via FIRST.org ↗

0.5%probability of exploitation in next 30 days

Lower Risk40th percentile+0.47%

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

15 pkgs affected

📦@apollo/federation-internals📦@apollo/federation-internals📦@apollo/federation-internals📦@apollo/federation-internals📦@apollo/federation-internals📦@apollo/gateway📦@apollo/gateway📦@apollo/gateway+7 more

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects npm packages — download data is not available via public APIs for these ecosystems.

Description

Apollo Federation is an architecture for declaratively composing APIs into a unified graph. Prior to 2.9.6, 2.10.5, 2.11.6, 2.12.3, and 2.13.2, a vulnerability exists in query plan execution within the gateway that may allow pollution of Object.prototype in certain scenarios. A malicious client may be able to pollute Object.prototype in gateway directly by crafting operations with field aliases and/or variable names that target prototype-inheritable properties. Alternatively, if a subgraph were to be compromised by a malicious actor, they may be able to pollute Object.prototype in gateway by crafting JSON response payloads that target prototype-inheritable properties. This vulnerability is fixed in 2.9.6, 2.10.5, 2.11.6, 2.12.3, and 2.13.2.

Affected Packages

15 total 15 fixed

Ecosystem	Package	Vulnerable range	Fix
📦npm	`@apollo/federation-internals`	all versions	2.9.6
📦npm	`@apollo/federation-internals`	≥ 2.10.0&&< 2.10.5	2.10.5
📦npm	`@apollo/federation-internals`	≥ 2.11.0&&< 2.11.6	2.11.6
📦npm	`@apollo/federation-internals`	≥ 2.12.0&&< 2.12.3	2.12.3
📦npm	`@apollo/federation-internals`	≥ 2.13.0&&< 2.13.2	2.13.2
📦npm	`@apollo/gateway`	all versions	2.9.6

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for @apollo/federation-internals. 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/federation-internals to 2.9.6 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-32621 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 CVE-2026-32621 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 CVE-2026-32621. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

Apollo Federation is an architecture for declaratively composing APIs into a unified graph. Prior to 2.9.6, 2.10.5, 2.11.6, 2.12.3, and 2.13.2, a vulnerability exists in query plan execution within the gateway that may allow pollution of Object.prototype in certain scenarios. A malicious client may be able to pollute Object.prototype in gateway directly by crafting operations with field aliases and/or variable names that target prototype-inheritable properties. Alternatively, if a subgraph were to be compromised by a malicious actor, they may be able to pollute Object.prototype in gateway by c

O3 Security · Impact-Aware SCA

Is CVE-2026-32621 in your dependencies?

O3 detects CVE-2026-32621 across npm dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.

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CVE-2026-32621