CVE-2026-21531

Azure SDK for Python Remote Code Execution Vulnerability

Deserialization of untrusted data in Azure SDK allows an unauthorized attacker to execute code over a network.

Affected

Microsoft · Azure AI Language Authoring

CVSS v3.1 MICROSOFT

9.8 CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

EPSS

2.58% chance of exploitation in the next 30 days, 85th percentile

Published

2026-02-10

Updated

2026-08-19

Proof-of-concept exploits (1)

• NetVanguard-cmd/CVE-2026-215312★ · 2026-02-11

Security advisories

• https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-21531
• advisories/GHSA-436v-jg82-p533

References

• CVE Record
• NVD entry

Related

• CVE-2025-11371
• CVE-2025-59536
• CVE-2026-2441
• CVE-2026-27597
• CVE-2026-3055
• CVE-2026-4447