What is CVE-2026-27448?

CVE-2026-27448 is a security advisory published by Microsoft Security Response Center (MSRC) with Low severity. pyOpenSSL allows TLS connection bypass via unhandled callback exception in set_tlsext_servername_callback

Which CVE IDs does CVE-2026-27448 cover?

CVE-2026-27448 covers the following CVE IDs: CVE-2026-27448. Each CVE has its own detail page on EchelonGraph Pulse with the synthesized EG score.

Which products are affected by CVE-2026-27448?

CVE-2026-27448 affects 3 products, including: azl3 pyOpenSSL 24.2.1-1 on Azure Linux 3.0; cbl2 pyOpenSSL 18.0.0-8 on CBL Mariner 2.0; cbl2 pyOpenSSL 18.0.0-8 on CBL-Mariner 2.0.

CVE-2026-27448Low

pyOpenSSL allows TLS connection bypass via unhandled callback exception in set_tlsext_servername_callback

Vendor

Microsoft Security Response Center (MSRC)

Published

May 31, 2026

Last Modified

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🔗 CVE IDs covered (1)

CVE-2026-27448 →

🎯 Affected products3

azl3 pyOpenSSL 24.2.1-1 on Azure Linux 3.0
cbl2 pyOpenSSL 18.0.0-8 on CBL Mariner 2.0
cbl2 pyOpenSSL 18.0.0-8 on CBL-Mariner 2.0

✅ Remediation

KBCBL-Mariner Releases (Security Update) — fixed build 24.2.1-2 KBRelease Notes (Security Update)

🔗 References (2)

advisoryhttps://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-27448
referencehttps://learn.microsoft.com/en-us/azure/azure-linux/tutorial-azure-linux-upgrade