Integer overflow in IBM Powervm Hypervisor
CVE-2026-16661
IBM PowerVM Hypervisor FW1120.00, FW1110.00 through FW1110.30, FW1060.00 through FW1060.80, and FW950.00 through FW950.H2 is affected by a vulnerability in the service processor mailbox interface. An attacker with authenticated service-level access to the FSP can exploit this vulnerability, allowing arbitrary code to be executed in the host firmware runtime, giving full control over the managed system, resulting in a confidentiality, integrity, and availability impact to the managed system.
Vulnerability class: Integer Overflow
CVSS v3 metric
CVSS v3 base score 8.2 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H.
Affected products
- Ibm Powervm Hypervisor — versions FW1120.00
Weakness classification (CWE)
References
- psirt@us.ibm.com (vendor-advisory, patch)
Frequently asked questions
- What is CVE-2026-16661?
- CVE-2026-16661 is a high-severity vulnerability in IBM Powervm Hypervisor, classified under Integer Overflow or Wraparound. CVSS score: 8.2/10. Published 2026-08-19.
- How severe is CVE-2026-16661?
- High severity. CVSS v3 base score is 8.2 out of 10.