What is CVE-2026-40691?

CVE-2026-40691 is a security advisory published by Microsoft Security Response Center (MSRC) with Medium severity. Packet of death for DNSCrypt over TCP

Which CVE IDs does CVE-2026-40691 cover?

CVE-2026-40691 covers the following CVE IDs: CVE-2026-40691. Each CVE has its own detail page on EchelonGraph Pulse with the synthesized EG score.

What is the CVSS v3 score of CVE-2026-40691?

CVE-2026-40691 has a CVSS v3 base score of 7.5, published by Microsoft Security Response Center (MSRC).

Which products are affected by CVE-2026-40691?

CVE-2026-40691 affects 1 product, including: azl3 unbound 1.25.1-1 on Azure Linux 3.0.

CVE-2026-40691MediumCVSS 7.5

Packet of death for DNSCrypt over TCP

Vendor

Microsoft Security Response Center (MSRC)

Published

July 23, 2026

Last Modified

—

🔗 CVE IDs covered (1)

CVE-2026-40691 →

🎯 Affected products1

azl3 unbound 1.25.1-1 on Azure Linux 3.0

✅ Remediation

KBCBL-Mariner Releases (Security Update) — fixed build 1.25.2-1

🔗 References (2)

advisoryhttps://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-40691
referencehttps://learn.microsoft.com/en-us/azure/azure-linux/tutorial-azure-linux-upgrade