Prototype Pollution in @Apollo Federation-Internals

CVE-2026-32621

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.

Vulnerability class: Prototype Pollution

Published · last modified .

CVSS v3 metric

CVSS v3 base score 9.9 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:L.

EPSS exploit prediction

EPSS: 0.006 (44.5th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 44th percentile — 44.5% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-32621: held from 0.005 to 0.006.

EPSS over last 30 days · oldest: 0.005 · newest: 0.006 · change: +0.000

Affected products

  • @Apollo Federation-Internals — versions >= 2.13.0-preview.0, < 2.13.2, >= 2.12.0-preview.0, < 2.12.3, >= 2.11.0-preview.0, < 2.11.6
  • @Apollo Gateway — versions >= 2.13.0-preview.0, < 2.13.2, >= 2.12.0-preview.0, < 2.12.3, >= 2.11.0-preview.0, < 2.11.6
  • @Apollo Query-Planner — versions >= 2.13.0-preview.0, < 2.13.2, >= 2.12.0-preview.0, < 2.12.3, >= 2.11.0-preview.0, < 2.11.6

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2026-32621?
CVE-2026-32621 is a critical-severity vulnerability in @Apollo Federation-Internals, classified under Improperly Controlled Modification of Object Prototype Attributes (Prototype Pollution). CVSS score: 9.9/10. Published 2026-03-16.
How severe is CVE-2026-32621?
Critical severity. CVSS v3 base score is 9.9 out of 10.
Is CVE-2026-32621 known to be exploited?
1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.