Status: UPDATED | Advisory ID: CVE-2026-98283
| CVE | CVE-2026-98283 |
| CVSS Score / Version | 8.8 (High) / CVSS v3.1 |
| Updated | 2026-10-07 |
| CVSS Vector | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H |
| CVSS Prose | attack vector is local; attack complexity is low; privileges required is low; user interaction is none; scope is changed; confidentiality impact is high; integrity impact is high; availability impact is high. |
| Affected products | Linux Kernel |
| Vendor | Product | Affected Versions | Patch Status |
|---|---|---|---|
| Linux | Linux Kernel |
| Subsystems | OT Supporting Infrastructure |
| Sectors | All Sectors |
In the Linux kernel, the following vulnerability has been resolved:
KVM: PPC: Book3S HV: fix use-after-free in kvmhv_emulate_tlbie_all_lpid()
kvmhv_emulate_tlbie_all_lpid() iterates the nested-guest IDR and drops
mmu_lock before calling kvmhv_emulate_tlbie_lpid(), but does not hold a
reference on the kvm_nested_guest pointer obtained from the IDR. A
concurrent vCPU issuing a single-LPID tlbie (is=2, ric=2) can race
through kvmhv_flush_nested() -> kvmhv_remove_nested() -> idr_remove /
--refcnt -> kvmhv_release_nested() -> kfree(gp) in that window, leaving
the iterating vCPU with a dangling pointer. The subsequent
mutex_lock(&gp->tlb_lock) and accesses to gp->shadow_pgtable,
gp->shadow_lpid and gp->l1_host all touch freed memory. The free path
is fully L1-controlled.
Fix this by incrementing gp->refcnt inside the loop before dropping
mmu_lock, mirroring what kvmhv_get_nested() does, and releasing the
reference with kvmhv_put_nested() after the per-guest work completes.
This is the same get/put discipline already used at every other
call site that drops mmu_lock while holding a nested-guest pointer. (NVD)
Monitor Linux's web page for any future patch releases.
| Source | Reference |
|---|---|
| NVD | https://nvd.nist.gov/vuln/detail/CVE-2026-98283 |
| CVE | https://www.cve.org/CVERecord?id=CVE-2026-98283 |