Unknown

CVE-2026-68428 — KVM: x86/mmu: Fix use-after-free on vendor module reload

In the Linux kernel, the following vulnerability has been resolved: KVM: x86/mmu: Fix use-after-free on vendor module reload mmu_destroy_caches() destroys pte_list_desc_cache and mmu_page_header_cache, but leaves both pointers unchanged. The pointers live in kvm.ko, and therefore survive when a vendor module is unloaded while kvm.ko remains loaded. If creation of pte_list_desc_cache fails during a subsequent vendor module load, its assignment sets pte_list_desc_cache to NULL and the error path calls mmu_destroy_caches(). mmu_page_header_cache still points to the cache destroyed during the preceding vendor module unload. Passing that stale pointer to kmem_cache_destroy() causes a slab use-after-free. Reproduce the issue on a v7.1.3 kernel with CONFIG_KASAN=y, CONFIG_KASAN_GENERIC=y, CONFIG_KVM=m, and CONFIG_KVM_INTEL=m. A one-shot test hook forces pte_list_desc_cache to NULL on the second invocation of kvm_mmu_vendor_module_init(): 1. Load kvm.ko and kvm-intel.ko, creating both caches. 2. Unload only kvm_intel, leaving kvm.ko loaded. 3. Reload kvm_intel and force initialization through the -ENOMEM path. KASAN reports: BUG: KASAN: slab-use-after-free in kvm_mmu_vendor_module_init+0x5b/0x170 [kvm] ... kmem_cache_destroy+0x21/0x1d0 kvm_mmu_vendor_module_init+0x5b/0x170 [kvm] ... Allocated by task 16817: __kmem_cache_create_args+0x12c/0x3b0 __kmem_cache_create.constprop.0+0xb6/0xf0 [kvm] kvm_mmu_vendor_module_init+0x13b/0x170 [kvm] ... Freed by task 16820: kmem_cache_destroy+0x117/0x1d0 kvm_mmu_vendor_module_exit+0x21/0x30 [kvm] Clear both pointers immediately after destroying their caches so that the stored state reflects the caches' lifetime and repeated cleanup is safe. With the fix applied, the same injected vendor module reload fails with -ENOMEM as expected and produces no KASAN report.

Published Aug 10, 2026 · Updated Oct 15, 2026 · Sources: NIST National Vulnerability Database, CVE Program (cve.org) e CISA ADP · CNA: Linux

Low

Who exploits it and how urgent it is

A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.

No exploitation signal in the sources consulted so far.

How the score was calculated

EPSS 0.2% (30-day exploitation probability)+1

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.

Exploitation

Not confirmed

Not in CISA KEV — an absence of record, not proof it is unexploited.

EPSS FIRST

0.17%

ahead of 6% of scored CVEs · Oct 30, 2026

Affects

Linux

CVSS base

—

Score not published yet.

Remediation

Fixes and mitigations documented by the sources — linked to the original advisory.

No fix documented by the sources we poll. That does not mean none exists: check the vendor advisory.

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 (Linux Linux).
No fix documented in the sources: reduce exposure and monitor the vendor advisory.
Search available logs for exploit probes, errors and authentication anomalies.

Affected scope

Vendor, product and versions as the sources word them.

Vendor	Product	Versions	Status	Source
Linux	Linux	≥ cb498ea2ce1d3f3c0bc0a2522241dca10263e437 and < 034b7fa1f5846d69eb51f12ce6d1c71871e83c2d≥ cb498ea2ce1d3f3c0bc0a2522241dca10263e437 and < 42272b0f239f3a89f9c26a01cc37aee06138b1b7≥ cb498ea2ce1d3f3c0bc0a2522241dca10263e437 and < 940950d5cd86f250dca578279ad5ca63b4e0986b≥ cb498ea2ce1d3f3c0bc0a2522241dca10263e437 and < 6f4be73880302d5642c83a0813fdfe1f5fd4b6e3≥ cb498ea2ce1d3f3c0bc0a2522241dca10263e437 and < 32b9f89ed9e6d7a45075d64089c254a7f6e13695≥ cb498ea2ce1d3f3c0bc0a2522241dca10263e437 and < ec9daa8fd1b6f45545c9839dca55bd867fad9e13≥ cb498ea2ce1d3f3c0bc0a2522241dca10263e437 and < 43cfb20d62ffe49626d62beecfc32eb6f262191c≥ cb498ea2ce1d3f3c0bc0a2522241dca10263e437 and < 52f2f7c30126037975389aa04d24c506a5177c35 and 1 more version 2.6.25	Vulnerable	CVE Program (cve.org) e CISA ADP

EPSS over time FIRST

Oct 15, 2026 → Oct 30, 2026 · 15 reading(s) · max 0.17%

Detection

Read off the CVSS vector and the weakness class. Starting points, not tested rules.

Not enough vector or weakness data: use the affected application’s logs as a starting point.

application logs

Timeline

What happened to this CVE, newest first.

2026
Record published
Oct 15, 2026
Affected products added · linux/linux
Oct 15, 2026 · CVE Program (cve.org) e CISA ADP
Source status changed · → Received
Oct 15, 2026 · NIST National Vulnerability Database
Record created in this database
Oct 15, 2026 · NIST National Vulnerability Database
CVE published
Aug 10, 2026 · Linux

Source activity

Repeated readings are counted rather than listed.

1× Official description updated · Oct 15, 2026 – Oct 15, 2026

References

8 on the record

git.kernel.org/stable/c/32b9f89ed9e6d7a45075d64089c254a7f6e13695
NIST National Vulnerability Database
git.kernel.org/stable/c/43cfb20d62ffe49626d62beecfc32eb6f262191c
NIST National Vulnerability Database
git.kernel.org/stable/c/ec9daa8fd1b6f45545c9839dca55bd867fad9e13
NIST National Vulnerability Database
git.kernel.org/stable/c/940950d5cd86f250dca578279ad5ca63b4e0986b
NIST National Vulnerability Database
git.kernel.org/stable/c/6f4be73880302d5642c83a0813fdfe1f5fd4b6e3
NIST National Vulnerability Database
git.kernel.org/stable/c/52f2f7c30126037975389aa04d24c506a5177c35
NIST National Vulnerability Database
git.kernel.org/stable/c/034b7fa1f5846d69eb51f12ce6d1c71871e83c2d
NIST National Vulnerability Database
git.kernel.org/stable/c/42272b0f239f3a89f9c26a01cc37aee06138b1b7
NIST National Vulnerability Database

Elsewhere on this site

Linux
every CVE for this vendor

Related CVEs (same products)

Unknown CVE-2026-99216 Drivers: hv: Don't reset VMBus connection state on error/exit paths 2d
Unknown CVE-2026-99215 power: supply: core: prevent unregistering a power supply while a callback runs 2d
Unknown CVE-2026-99207 scsi: target: Disable interrupts while holding delayed_cmd_lock 2d
Unknown CVE-2026-99208 drm/xe/oa: Zero OA buffer at allocation 2d
Unknown CVE-2026-99209 drm/xe: skip eviction of a BO with no resource 2d
Unknown CVE-2026-99210 accel/rocket: clear rdev on device init failure 2d

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 CVSS score published by NVD, the CNA, CISA or GitHub so far.
No fixed version, patch or mitigation documented.
No CISA SSVC assessment.
No CWE classification.
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-2026-68428 is "KVM: x86/mmu: Fix use-after-free on vendor module reload", rated Unknown. It affects Linux (Linux); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. EPSS 0.17% 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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