CVE-2026-80684: KVM: s390: pci: Fix NULL dereference on AIBV allocation failure

mediumCVSS 5.5CVE-2026-80684

CSIRTS triage

vendor: Linux product: Linux kernel Memory corruption

What: NULL pointer dereference in KVM s390 PCI code when AIBV allocation fails.
Who is affected: s390 architecture systems running KVM hypervisor on vulnerable Linux kernels.
Urgency: Medium priority; not exploited but can cause guest VM crashes on allocation failures.
Action: Update to a patched Linux kernel version with NULL dereference handling for KVM s390 PCI AIBV allocation.

AI-assisted analysis generated from the source advisory — verify against the original.

⚡ Watch Linux kernel

Get an email when a new Linux kernel advisory drops — max one per day, one-click unsubscribe.

Details

Source: Microsoft Security Response Center (INTL · vendor-psirt · site)
Severity: medium — CVSS 5.5
Published: 2026-08-11
Exploitation: Not in CISA KEV at last sync

Original advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-80684

Exploitation outlook

EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.

Low exploitation riskCVE-2026-806840.14% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 4% of all EPSS-scored CVEs.

Referenced CVEs

CVE	CSIRTS overview	External
CVE-2026-80684	coverage & exploitation status	NVD · CVE.org

Same CVEs, other sources

How other CERTs, PSIRTs and databases cover the vulnerabilities in this advisory.

criticalCVE-2026-80684: In the Linux kernel, the following vulnerability has been resolved: KVM: s390: pci: Fix NULL d…nvd

Recent advisories for KVM

A cluster of recent advisories against the same product widens the attack surface — attackers routinely chain freshly published CVEs on one product, so review these together.

unknownCVE-2026-80699: In the Linux kernel, the following vulnerability has been resolved: KVM: arm64: vgic: Avoid do…nvd · 2026-08-28
criticalCVE-2026-80684: In the Linux kernel, the following vulnerability has been resolved: KVM: s390: pci: Fix NULL d…nvd · 2026-08-28
highCVE-2026-80665: In the Linux kernel, the following vulnerability has been resolved: KVM: arm64: nv: Inject SEA…nvd · 2026-08-28
highCVE-2026-74607: In the Linux kernel, the following vulnerability has been resolved: KVM: SVM: Serialize access…nvd · 2026-08-22
unknownUSN-8667-1: Linux kernel (KVM) vulnerabilitiesubuntu · 2026-08-21
criticalCVE-2026-74568: In the Linux kernel, the following vulnerability has been resolved: KVM: arm64: vgic: Fix race…nvd · 2026-08-15