CVE-2025-39845: Linux kernel · x86/mm/64: define ARCH_PAGE_TABLE_SYNC_MASK and arch_sync_kernel_mappings()
Affects Linux kernelSource CVE Database V5
Not known to be exploited · fixed in b7f4051dd3388edd30e9a6077c05c486aa31e0d4 : patch Linux kernel soon.
Data as of 10 Nov 2026, 12:50 UTC
Rated High by Threat Radar's AI analysis · No CVSS score from NVD or the CNA
Thin evidence
One scorer or none- Patch
- Available – fixed in b7f4051dd3388edd30e9a6077c05c486aa31e0d4, 6659d027998083fbb6d42a165b0c90dc2e8ba989, 744ff519c72de31344a627eaf9b24e9595aae554 +3
Exploitation evidence
Disclosed: evidence found.
CVE published 19 Sep 2025
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 10 Nov 2026.
What to do
Upgrade to a fixed release listed under Affected software.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| LinuxLinux | Affected
| Fixed in
|
| LinuxLinux | Affected
| Fixed in
|
| LinuxLinux | Affected
| Fixed in
|
| LinuxLinux | Affected
| Fixed in
|
| LinuxLinux | Affected
| Fixed in
|
| LinuxLinux | Affected
| Fixed in
|
AI-suggested
A fix is available and has been applied in multiple Linux kernel commits. Systems running affected versions should upgrade to a fixed kernel version incorporating these patches. No additional mitigation is required once the kernel is updated.
Description
CVE-2025-39845 is a vulnerability in the Linux kernel affecting version 5.13 where page tables were not properly synchronized during kernel memory population operations. This caused intermittent boot failures and kernel crashes related to page faults on systems using 4-level paging and large persistent memory. The issue was fixed by defining ARCH_PAGE_TABLE_SYNC_MASK and arch_sync_kernel_mappings() to ensure proper synchronization of page tables during p*d_populate_kernel() calls.
References
- git.kernel.org/stable/c/744ff519c72de31344a627eaf9b24e9595aae554 (opens in a new tab)
- git.kernel.org/stable/c/5f761d40ee95d2624f839c90ebeef2d5c55007f5 (opens in a new tab)
- git.kernel.org/stable/c/26ff568f390a531d1bd792e49f1a401849921960 (opens in a new tab)
- git.kernel.org/stable/c/b7f4051dd3388edd30e9a6077c05c486aa31e0d4 (opens in a new tab)
- git.kernel.org/stable/c/6bf9473727569e8283c1e2445c7ac42cf4fc9fa9 (opens in a new tab)
- git.kernel.org/stable/c/6659d027998083fbb6d42a165b0c90dc2e8ba989 (opens in a new tab)
- lists.debian.org/debian-lts-announce/2025/10/msg00008.html (opens in a new tab)
- cert-portal.siemens.com/productcert/html/ssa-032379.html (opens in a new tab)
- cert-portal.siemens.com/productcert/html/ssa-019113.html (opens in a new tab)
- cert-portal.siemens.com/productcert/html/ssa-457936.html (opens in a new tab)