What is CVE-2026-9831?

CVE-2026-9831 is a medium-severity vulnerability in Extreme Networks Platform One, classified under Concurrent Execution using Shared Resource with Improper Synchronization (Race Condition). CVSS score: 6.3/10. Published 2026-05-29.

How severe is CVE-2026-9831?

Medium severity. CVSS v3 base score is 6.3 out of 10.

Vulnerability in Extreme Networks Platform One

CVE-2026-9831

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.

Vulnerability class: Race Condition

Published 2026-05-29 · last modified 2026-07-22.

CVSS v3 metric

CVSS v3 base score 6.3 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:N/A:N.

EPSS exploit prediction

EPSS: 0.003 (16.2th percentile), scored 2026-10-19.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 16th percentile — 16.2% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.002 · newest: 0.003 · change: +0.001

Affected products

Extreme Networks Platform One — versions 0, 25.10.0-104

Weakness classification (CWE)

References

1c053176-eef3-4d6a-ae0b-24728c86587b (vendor-advisory)

Frequently asked questions

What is CVE-2026-9831?: CVE-2026-9831 is a medium-severity vulnerability in Extreme Networks Platform One, classified under Concurrent Execution using Shared Resource with Improper Synchronization (Race Condition). CVSS score: 6.3/10. Published 2026-05-29.
How severe is CVE-2026-9831?: Medium severity. CVSS v3 base score is 6.3 out of 10.