Expired Pointer Dereference Affecting kernel-rt-doc package, versions *
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
Do your applications use this vulnerable package?
In a few clicks we can analyze your entire application and see what components are vulnerable in your application, and suggest you quick fixes.
Test your applications- Snyk IDSNYK-CENTOS7-KERNELRTDOC-18687295
- published12 Aug 2026
- disclosed10 Aug 2026
Introduced: 10 Aug 2026
NewCVE-2026-68428 (opens in a new tab)How to fix?
There is no fixed version for Centos:7 kernel-rt-doc.
NVD Description
Note: Versions mentioned in the description apply only to the upstream kernel-rt-doc package and not the kernel-rt-doc package as distributed by Centos.
See How to fix? for Centos:7 relevant fixed versions and status.
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():
- Load kvm.ko and kvm-intel.ko, creating both caches.
- Unload only kvm_intel, leaving kvm.ko loaded.
- 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.
References
- https://access.redhat.com/security/cve/CVE-2026-68428
- https://git.kernel.org/stable/c/32b9f89ed9e6d7a45075d64089c254a7f6e13695
- https://git.kernel.org/stable/c/43cfb20d62ffe49626d62beecfc32eb6f262191c
- https://git.kernel.org/stable/c/52f2f7c30126037975389aa04d24c506a5177c35
- https://git.kernel.org/stable/c/6f4be73880302d5642c83a0813fdfe1f5fd4b6e3
- https://git.kernel.org/stable/c/ec9daa8fd1b6f45545c9839dca55bd867fad9e13