SB20260918204 - Reliance on undefined behavior in Linux kernel iommu amd driver
Published: September 18, 2026
Security Bulletin ID
SB20260918204
CSH Severity
Low
Patch available
YES
Number of vulnerabilities
1
Exploitation vector
Local access
Highest impact
Information disclosure
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 1 vulnerability.
1) Reliance on undefined behavior (CVE-ID: CVE-2026-92505)
CWE-ID: CWE-758 - Reliance on Undefined, Unspecified, or Implementation-Defined Behavior
CVSSv4: 0 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:N/SC:N/SI:N/SA:N]
The vulnerability allows a local user to trigger undefined behavior.
The vulnerability exists due to reliance on undefined behavior in the AMD IOMMU devid_write debugfs function when processing a device ID for which no matching PCI segment is found. A local user can write such a device ID to the debugfs interface to trigger undefined behavior.
Remediation
Install update from vendor's website.