CVE-2025-21696MediumMicrosoft 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-2025-21696 — azl3 kernel

Published
June 3, 2026
Last Modified
—

🔗 CVE IDs covered (1)

CVE-2025-21696 →

📋 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-2025-21696. This page also shows what EchelonGraph holds for CVE-2025-21696, 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 products23

  • 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 6.6.96.2-1 on Azure Linux 3.0
  • azl3 kernel 6.6.96.2-2 on Azure Linux 3.0

✅ Updates Microsoft lists: 2 updates

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

KB articleUpdateFixed build
—Security Update—
—Security Update—

🧭 EchelonGraph on CVE-2025-21696

EchelonGraph score
5.5 MEDIUM
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: mm: clear uffd-wp PTE/PMD state on mremap() When mremap()ing a memory region previously registered with userfaultfd as write-protected but without UFFD_FEATURE_EVENT_REMAP, an inconsistency in flag clearing leads to a mismatch between the vma flags (which have uffd-wp cleared) and the pte/pmd flags (which do not have uffd-wp cleared). This mismatch causes a subsequent mprotect(PROT_WRITE) to trigger a warning in page_table_check_pte_flags() due to setting the pte to writable while uffd-wp is still set. Fix this by always explicitly clearing the uffd-wp pte/pmd flags on any such mremap() so that the values are consistent with the existing clearing of VM_UFFD_WP. Be careful to clear the logical flag regardless of its physical form; a PTE bit, a swap PTE bit, or a PTE marker. Cover PTE, huge PMD and hugetlb paths.

Published by kernel.org, the CVE Numbering Authority that assigned CVE-2025-21696, 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)