CVE-2026-16661: CWE-190 Integer Overflow or Wraparound in IBM PowerVM Hypervisor
CVE-2026-16661 is a high-severity integer overflow vulnerability in IBM PowerVM Hypervisor's service processor mailbox interface. It affects multiple firmware versions and allows an attacker with authenticated service-level access to execute arbitrary code in the host firmware runtime. This leads to full control over the managed system, impacting confidentiality, integrity, and availability.
AI Analysis
Technical Summary
IBM PowerVM Hypervisor versions FW1120.00, FW1110.00 through FW1110.30, FW1060.00 through FW1060.80, and FW950.00 through FW950.H2 contain an integer overflow or wraparound vulnerability (CWE-190) in the service processor mailbox interface. An attacker with authenticated service-level access to the Flexible Service Processor (FSP) can exploit this flaw to execute arbitrary code within the host firmware runtime environment. This exploitation results in complete control over the managed system, compromising confidentiality, integrity, and availability of the system.
Potential Impact
Successful exploitation allows an attacker with authenticated service-level access to gain arbitrary code execution in the host firmware runtime, resulting in full control over the managed system. This compromises confidentiality, integrity, and availability of the system.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance.
CVE-2026-16661: CWE-190 Integer Overflow or Wraparound in IBM PowerVM Hypervisor
Description
CVE-2026-16661 is a high-severity integer overflow vulnerability in IBM PowerVM Hypervisor's service processor mailbox interface. It affects multiple firmware versions and allows an attacker with authenticated service-level access to execute arbitrary code in the host firmware runtime. This leads to full control over the managed system, impacting confidentiality, integrity, and availability.
CVSS v3.1
Score 8.2high
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
IBM PowerVM Hypervisor versions FW1120.00, FW1110.00 through FW1110.30, FW1060.00 through FW1060.80, and FW950.00 through FW950.H2 contain an integer overflow or wraparound vulnerability (CWE-190) in the service processor mailbox interface. An attacker with authenticated service-level access to the Flexible Service Processor (FSP) can exploit this flaw to execute arbitrary code within the host firmware runtime environment. This exploitation results in complete control over the managed system, compromising confidentiality, integrity, and availability of the system.
Potential Impact
Successful exploitation allows an attacker with authenticated service-level access to gain arbitrary code execution in the host firmware runtime, resulting in full control over the managed system. This compromises confidentiality, integrity, and availability of the system.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- ibm
- Date Reserved
- 2026-07-22T19:47:20.654Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a86098facd9273b498b4beb
Added to database: 08/19/2026, 19:52:47 UTC
Last enriched: 08/19/2026, 20:24:14 UTC
Last updated: 08/20/2026, 01:12:12 UTC
Views: 3
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