CVE-2026-52968: KVM: s390: pci: fix GAIT table indexing due to double-scaling pointer arithmetic

Severity: high (CVSS 7.1 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.2% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-06-24 · updated 2026-10-19
Weakness: CWE-125

Description

In the Linux kernel, the following vulnerability has been resolved: KVM: s390: pci: fix GAIT table indexing due to double-scaling pointer arithmetic kvm_s390_pci_aif_enable(), kvm_s390_pci_aif_disable(), and aen_host_forward() index the GAIT by manually multiplying the index with sizeof(struct zpci_gaite). Since aift->gait is already a struct zpci_gaite pointer, this double-scales the offset, accessing element aisb*16 instead of aisb. This causes out-of-bounds accesses when aisb >= 32 (with ZPCI_NR_DEVICES=512) Fix by removing the erroneous sizeof multiplication.

Affected products

Linux kernel: from 6.0 before 6.1.175; from 6.2 before 6.6.141; from 6.7 before 6.12.91; from 6.13 before 6.18.33; from 6.19 before 7.0.10; 7.1-rc1, 7.1-rc2, 7.1-rc3 — fixed in 6.1.175, 6.12.91, 6.18.33, 6.6.141, 7.0.10

How to fix

Upgrade to a fixed version: Linux kernel 6.1.175, 6.12.91, 6.18.33, 6.6.141. Check the vendor advisory for mitigations.

References

Get alerted when CVE-2026-52968 or the next vulnerability affects your stack