What is CVE-2026-21226?

CVE-2026-21226 is a high-severity vulnerability in Microsoft Azure_core_shared_client_library, classified under Deserialization of Untrusted Data. CVSS score: 7.5/10. Published 2026-01-13.

How severe is CVE-2026-21226?

High severity. CVSS v3 base score is 7.5 out of 10.

Deserialization in Microsoft Azure_core_shared_client_library

CVE-2026-21226

Deserialization of untrusted data in Azure Core shared client library for Python allows an authorized attacker to execute code over a network.

Vulnerability class: Insecure Deserialization

EPSS: 0.008 (51.2th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H.

Affected products

Microsoft Azure_core_shared_client_library
Microsoft Azure Core Shared Client Library For Python — versions 1.1.0

Weakness classification (CWE)

CWE-502 — Deserialization of Untrusted Data

References

secure@microsoft.com (vendor-advisory, patch, Vendor Advisory)

Frequently asked questions

What is CVE-2026-21226?: CVE-2026-21226 is a high-severity vulnerability in Microsoft Azure_core_shared_client_library, classified under Deserialization of Untrusted Data. CVSS score: 7.5/10. Published 2026-01-13.
How severe is CVE-2026-21226?: High severity. CVSS v3 base score is 7.5 out of 10.