CVE-2026-9831 PUBLISHED

ExtremeCloud IQ Cross Tenant Data Exposure via Extreme Platform One Authentication Race Condition

Assigner: ExtremeNetworks
Reserved: 28.05.2026 Published: 29.05.2026 Updated: 29.05.2026

A race condition in the shared Extreme Platform ONE IAM Gateway API-key authentication path could, under specific high-concurrency traffic conditions, intermittently allow requests authenticated with an Extreme Platform ONE /IAM-issued API key to receive response data for another tenant. The issue was observed through ExtremeCloud IQ/XIQ API endpoints and validated against both XIQ/XAPI and Extreme Platform ONE /Common Services API paths. XIQ-native tokens and standard OAuth/Bearer JWT authentication were not affected.

Metrics

CVSS 3.1

CVSS Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:N/A:N
CVSS Score: 6.3

Attack Vector	Network	Scope	Changed
Attack Complexity	High	Confidentiality Impact	High
Privileges Required	Low	Integrity Impact	None
User Interaction	None	Availability Impact	None

CVSS 3.1

Product Status

Vendor	Extreme Networks
Product	Extreme Platform ONE
Versions	Default: unaffected affected from 0 to 25.10.0-104 (excl.) Version 25.10.0-104 is unaffected

Credits

Sebastian Koller of Iteas IT Services GmbH (Austria) for responsible discovery and disclosure of this vulnerability. finder
Sebastian Koller of Iteas IT Services GmbH (Austria) for responsible coordination and providing detailed evidence supporting root cause identification. reporter

References

https://community.extremenetworks.com/t5/security-advisories-formerly/sa-2026-048-extremecloud-iq-cross-tenant-data-exposure-via/ba-p/121851

Problem Types

CWE-362: Concurrent Execution using Shared Resource with Improper Synchronization (Race Condition) CWE
CWE-488 Exposure of data element to wrong session CWE

Impacts

CAPEC-74: Manipulating State