CVE-2025-38681 — mm/ptdump: take the memory hotplug lock inside ptdump_walk_pgd()
In the Linux kernel, the following vulnerability has been resolved: mm/ptdump: take the memory hotplug lock inside ptdump_walk_pgd() Memory hot remove unmaps and tears down various kernel page table regions as required. The ptdump code can race with concurrent modifications of the kernel page tables. When leaf entries are modified concurrently, the dump code may log stale or inconsistent information for a VA range, but this is otherwise not harmful. But when intermediate levels of kernel page table are freed, the dump code will continue to use memory that has been freed and potentially reallocated for another purpose. In such cases, the ptdump code may dereference bogus addresses, leading to a number of potential problems. To avoid the above mentioned race condition, platforms such as arm64, riscv and s390 take memory hotplug lock, while dumping kernel page table via the sysfs interface /sys/kernel/debug/kernel_page_tables. Similar race condition exists while checking for pages that might have been marked W+X via /sys/kernel/debug/kernel_page_tables/check_wx_pages which in turn calls ptdump_check_wx(). Instead of solving this race condition again, let's just move the memory hotplug lock inside generic ptdump_check_wx() which will benefit both the scenarios. Drop get_online_mems() and put_online_mems() combination from all existing platform ptdump code paths.
Who exploits it and how urgent it is
A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.
How the score was calculated
- EPSS 0.1% (30-day exploitation probability)+0
- Technical severity (medium)+3
The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).
Triage
Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.
Remediation
Fixes and mitigations documented by the sources — linked to the original advisory.
- Documented patch — git.kernel.org (NIST National Vulnerability Database)
- Documented patch — git.kernel.org (NIST National Vulnerability Database)
- Documented patch — git.kernel.org (NIST National Vulnerability Database)
- Documented patch — git.kernel.org (NIST National Vulnerability Database)
- Documented patch — git.kernel.org (NIST National Vulnerability Database)
- Documented patch — git.kernel.org (NIST National Vulnerability Database)
- Documented patch — git.kernel.org (NIST National Vulnerability Database)
- Documented patch — git.kernel.org (NIST National Vulnerability Database)
First 24 hours
Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.
- Identify exposed assets running the affected vendor/product/version combinations (Debian Debian Linux, Linux Linux, Linux Linux Kernel).
- Apply the fixed version or the patch documented under Remediation.
- Search available logs for exploit probes matching the vulnerability class (logic error), errors and authentication anomalies.
Affected scope
Vendor, product and versions as the sources word them.
| Vendor | Product | Versions | Status | Source |
|---|---|---|---|---|
| Debian | Debian Linux | version 11.0 | Vulnerable | NIST National Vulnerability Database |
| Linux | Linux |
≥ bbd6ec605c0fc286c3f8ce60b4ed44635361d58b and < 3ee9a8c27bfd72c3f465004fa8455785d61be5e8version 5.7≥ bbd6ec605c0fc286c3f8ce60b4ed44635361d58b and < 59305202c67fea50378dcad0cc199dbc13a0e99a≥ bbd6ec605c0fc286c3f8ce60b4ed44635361d58b and < ca8c414499f2e5337a95a76be0d21b728ee31c6b≥ bbd6ec605c0fc286c3f8ce60b4ed44635361d58b and < 67995d4244694928ce701928e530b5b4adeb17b4≥ bbd6ec605c0fc286c3f8ce60b4ed44635361d58b and < ff40839e018b82c4d756d035f34a63aa2d93be83≥ bbd6ec605c0fc286c3f8ce60b4ed44635361d58b and < 1636b5e9c3543b87d673e32a47e7c18698882425≥ bbd6ec605c0fc286c3f8ce60b4ed44635361d58b and < ac25ec5fa2bf6e606dc7954488e4dded272fa9cd and 1 more≥ bbd6ec605c0fc286c3f8ce60b4ed44635361d58b and < 69bea84b06b5e779627e7afdbf4b60a7d231c76f |
Vulnerable | CVE Program (cve.org) e CISA ADP |
| Linux | Linux Kernel | ≥ 6.16 and < 6.16.2≥ 6.13 and < 6.15.11≥ 6.7 and < 6.12.43≥ 6.2 and < 6.6.103≥ 5.16 and < 6.1.149≥ 5.11 and < 5.15.190≥ 5.7 and < 5.10.241 | Vulnerable | NIST National Vulnerability Database |
Attack characteristics
The CVSS vector, decoded. It describes the attack, not your exposure to it.
Every base score collected
Sources score independently and may disagree; each row says who scored it and under which version.
| Score | Version | Severity | Expl. | Impact | Scored by |
|---|---|---|---|---|---|
| 4.7 | CVSS 3.1 | Medium | 1.0 | 3.6 | nvd@nist.gov via NIST National Vulnerability Database |
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H (score shown at the top: nvd@nist.gov) Weakness MITRE
Weakness class according to MITRE’s CWE catalog.
Detection
Read off the CVSS vector and the weakness class. Starting points, not tested rules.
- Local/physical vector: focus on endpoint telemetry (EDR) from affected hosts.
Timeline
What happened to this CVE, newest first.
- 2026
- Affected products added · linux/linux
- Record published
- Fix documented
- CVSS changed · 4.7
- Source status changed · → Modified
- Record created in this database
- 2025
- CVE published
Source activity
Repeated readings are counted rather than listed.
- 1× Official description updated · Oct 15, 2026 – Oct 15, 2026
References
13 on the record
- git.kernel.org/stable/c/1636b5e9c3543b87d673e32a47e7c18698882425
- git.kernel.org/stable/c/ac25ec5fa2bf6e606dc7954488e4dded272fa9cd
- git.kernel.org/stable/c/59305202c67fea50378dcad0cc199dbc13a0e99a
- git.kernel.org/stable/c/ca8c414499f2e5337a95a76be0d21b728ee31c6b
- git.kernel.org/stable/c/3ee9a8c27bfd72c3f465004fa8455785d61be5e8
- git.kernel.org/stable/c/69bea84b06b5e779627e7afdbf4b60a7d231c76f
- git.kernel.org/stable/c/67995d4244694928ce701928e530b5b4adeb17b4
- git.kernel.org/stable/c/ff40839e018b82c4d756d035f34a63aa2d93be83
- cert-portal.siemens.com/productcert/html/ssa-032379.html
- cert-portal.siemens.com/productcert/html/ssa-457936.html
- lists.debian.org/debian-lts-announce/2025/10/msg00007.html
- cert-portal.siemens.com/productcert/html/ssa-019113.html
- lists.debian.org/debian-lts-announce/2025/10/msg00008.html
Elsewhere on this site
Related CVEs (same products)
- Critical CVE-2026-99999 ipv4: validate checksum_start before completing checksum 14h
- Unknown CVE-2026-98432 ipv4: free inet_opt and ireq_opt after an RCU grace period 14h
- Unknown CVE-2026-98424 wifi: cfg80211: undo netns switch if renaming the wiphy fails 1d
- Unknown CVE-2026-98425 wifi: mac80211: don't warn when an IBSS has no channel to scan 1d
- Unknown CVE-2026-98426 wifi: mwifiex: fix IRQ leak using wrong index in MSI-X error path 1d
- Unknown CVE-2026-98427 net/sched: codel: bound the dropping loop per dequeue call 1d
Not in any source we poll
Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.
- No CISA SSVC assessment.
- No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
- No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
- No exploit packet captures, log samples, or incident case IDs supplied.
Answered from this record
Text assembled only from the fields above — no additional claims.
What should defenders know first?
CVE-2025-38681 is "mm/ptdump: take the memory hotplug lock inside ptdump_walk_pgd()", rated Medium. It affects Debian Linux (Debian); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 4.7 describes technical severity. EPSS 0.13% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.
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