CVE-2025-39859MediumMicrosoft CVSS 5.5CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Microsoft security update for CVE-2025-39859 — azl3 kernel

Published
June 3, 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-2025-39859. This page also shows what EchelonGraph holds for CVE-2025-39859, 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 products22

  • azl3 kernel 6.6.104.2-4 on Azure Linux 3.0
  • azl3 kernel 6.6.112.1-2 on Azure Linux 3.0
  • azl3 kernel 6.6.117.1-1 on Azure Linux 3.0
  • azl3 kernel 6.6.119.3-1 on Azure Linux 3.0
  • azl3 kernel 6.6.119.3-3 on Azure Linux 3.0
  • azl3 kernel 6.6.121.1-1 on Azure Linux 3.0
  • azl3 kernel 6.6.126.1-1 on Azure Linux 3.0
  • azl3 kernel 6.6.130.1-3 on Azure Linux 3.0
  • azl3 kernel 6.6.134.1-2 on Azure Linux 3.0
  • azl3 kernel 6.6.137.1-2 on Azure Linux 3.0
  • azl3 kernel 6.6.138.1-1 on Azure Linux 3.0
  • azl3 kernel 6.6.139.1-1 on Azure Linux 3.0
  • azl3 kernel 6.6.141.1-1 on Azure Linux 3.0
  • azl3 kernel 6.6.143.1-1 on Azure Linux 3.0
  • azl3 kernel 6.6.144.1-1 on Azure Linux 3.0
  • azl3 kernel 6.6.145.2-1 on Azure Linux 3.0
  • azl3 kernel 6.6.150.1-1 on Azure Linux 3.0
  • azl3 kernel 6.6.152.1-1 on Azure Linux 3.0
  • azl3 kernel 6.6.157.1-1 on Azure Linux 3.0
  • azl3 kernel 6.6.159.1-1 on Azure Linux 3.0
  • azl3 kernel 6.6.161.1-1 on Azure Linux 3.0
  • azl3 kernel 6.6.96.2-2 on Azure Linux 3.0

✅ 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 Update—

🧭 EchelonGraph on CVE-2025-39859

EchelonGraph score
7.8 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

In the Linux kernel, the following vulnerability has been resolved: ptp: ocp: fix use-after-free bugs causing by ptp_ocp_watchdog The ptp_ocp_detach() only shuts down the watchdog timer if it is pending. However, if the timer handler is already running, the timer_delete_sync() is not called. This leads to race conditions where the devlink that contains the ptp_ocp is deallocated while the timer handler is still accessing it, resulting in use-after-free bugs. The following details one of the race scenarios. (thread 1) | (thread 2) ptp_ocp_remove() | ptp_ocp_detach() | ptp_ocp_watchdog() if (timer_pending(&bp->watchdog))| bp = timer_container_of() timer_delete_sync() | | devlink_free(devlink) //free | | bp-> //use Resolve this by unconditionally calling timer_delete_sync() to ensure the timer is reliably deactivated, preventing any access after free.

Published by kernel.org, the CVE Numbering Authority that assigned CVE-2025-39859, 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)