ReviewHigh

CVE-2026-74515

Linux

In the Linux kernel, the following vulnerability has been resolved: KVM: s390: pci: Reject adapter interrupt forwarding if already enabled The MPCIFC instruction doesn't allow registering adapter interrupts without first unregistering. So reject any request to enable interrupt forwarding if its already enabled for the zPCI device. This also fixes overwriting and thus leaking resources when the ioctl is called multiple times for the same device.

CVSS: 8.8
EPSS: -
CISA KEV: Not listed
Published: 2026.08.15

PRIORITY ASSESSMENT

Review

The CVSS severity warrants an early asset and exposure review.

Known exploitationNot established by KEV

Exploit probability-

Technical severityCVSS 8.8

Vulnerability overview

Affected product and versions

Product: Linux
Affected versions: >= 3c5a1b6f0a18520a0edd0600fef6f1a8553b8fdc < 642d2d1067f7c4d753ae0e3ba5bc98b43cfe3c70, >= 3c5a1b6f0a18520a0edd0600fef6f1a8553b8fdc < 78d9648e7e960546d5b72504a0b0358cd8bb1e9d, >= 3c5a1b6f0a18520a0edd0600fef6f1a8553b8fdc < 6be1ff49ba81f96a6fa55915e6d920be43ac57cc, >= 3c5a1b6f0a18520a0edd0600fef6f1a8553b8fdc < 6837f0ae85fd54cf64c8a0c7c530bba2fae0a207, >= 3c5a1b6f0a18520a0edd0600fef6f1a8553b8fdc < 591952b63a9f976da7d49f719f36ec826ee2a575, >= 3c5a1b6f0a18520a0edd0600fef6f1a8553b8fdc < 8fa01be5a6149404adb82c0979a78f6347edd3ef, >= 6.0
Fixed versions: No verified fixed-version field is available yet

Recommended response sequence

Confirm exposure before applying a vendor-supported change.

Full remediation guide

1
Identify
Confirm that Linux and an affected version are present.
2
Prioritize
Combine exploitation signals with asset exposure and business criticality.
3
Remediate
Follow the vendor advisory or supported update path and preserve rollback options.
4
Verify
Recheck the version, service health, access paths, and relevant logs.

Technical data

CVSS vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
CWE: Not available