Review reviewHigh

CVE-2025-40117

Linux

In the Linux kernel, the following vulnerability has been resolved: misc: pci_endpoint_test: Fix array underflow in pci_endpoint_test_ioctl() Commit eefb83790a0d ("misc: pci_endpoint_test: Add doorbell test case") added NO_BAR (-1) to the pci_barno enum which, in practical terms, changes the enum from an unsigned int to a signed int. If the user passes a negative number in pci_endpoint_test_ioctl() then it results in an array underflow in pci_endpoint_test_bar().

CVSS: 7.8
EPSS: -
CISA KEV: Not listed
Published: 2025.11.12

PRIORITY ASSESSMENT

Review review

The CVSS severity warrants an early asset and exposure review.

Known exploitationNot established by KEV

Exploit probability-

Technical severityCVSS 7.8

Vulnerability overview

Affected product and versions

Product: Linux
Affected versions: >= eefb83790a0dda112d1755e4f5e213738d717e76 < 6df3687922570f753574c40b35e83b26b32292d0, >= eefb83790a0dda112d1755e4f5e213738d717e76 < 1ad82f9db13d85667366044acdfb02009d576c5a, >= 6.17
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:U/C:H/I:H/A:H
CWE: Not available