CVE-2026-40170HighMicrosoft CVSS 7.5CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Microsoft security update for CVE-2026-40170 — azl4 samba 2:4.23.7-4.azl4 on Azure Linux 4.0

Published
June 2, 2026
Last Modified
—

🔗 CVE IDs covered (1)

📋 Microsoft's advisory

EchelonGraph does not copy Microsoft's advisory page: its FAQ and remediation text are not shown here. Read the advisory on https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-40170. This page also shows what EchelonGraph holds for CVE-2026-40170, with the description from its CVE record, which the CVE Numbering Authority that assigned the CVE wrote: for a CVE Microsoft assigned, often in the words of Microsoft's own advisory.

🎯 Affected products1

  • azl4 samba 2:4.23.7-4.azl4 on Azure Linux 4.0

✅ Updates Microsoft lists: 1 update

1 row: one per KB article or update, update type and fixed build. Their details are on Microsoft's advisory.

KB articleUpdateFixed build
—Security Update2:4.23.13-3.azl4

🧭 EchelonGraph on CVE-2026-40170

EchelonGraph score
7.5 HIGH
CISA KEV
Not listed
Fix status
A fix is available — apply it.

Description from the CVE record (CVE.org), as published by its numbering authority

ngtcp2 is a C implementation of the IETF QUIC protocol. In versions prior to 1.22.1, ngtcp2_qlog_parameters_set_transport_params() serializes peer transport parameters into a fixed 1024-byte stack buffer without bounds checking. When qlog is enabled, a remote peer can send sufficiently large transport parameters during the QUIC handshake to cause writes beyond the buffer boundary, resulting in a stack buffer overflow. This affects deployments that enable the qlog callback and process untrusted peer transport parameters. This issue has been fixed in version 1.22.1. If developers are unable to immediately upgrade, they can disable the qlog on client.

Published by GitHub, Inc., the CVE Numbering Authority that assigned CVE-2026-40170, in its CVE record at CVE.org; reused under the CVE Program's Terms of Use (its licence and MITRE's copyright notice are in our Terms of Service).

🔗 References (2)