CVE-2026-17100 Power System Out-of-bounds Write

High 8.2 Published 19 Aug 2026 Updated 21 Aug 2026

Authenticated attackers can execute arbitrary code in host firmware via a service processor mailbox interface vulnerability, gaining full system control.

Exploited in the wild: Not known
Login needed: An administrator
Attackable: Local or same network only
Victim action needed: Not needed
Fix: None listed

What is CVE-2026-17100?

CVE-2026-17100 is a high-severity memory corruption vulnerability in IBM Power Systems Firmware, published on 19 Aug 2026. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

Power Systems Firmware FW1120.00, FW1110.00 through FW1110.30, FW1060.00 through FW1060.80, FW950.00 through FW950.H2, OP940.00 through OP940.a1, and OP940.00 - OP940.81 is affected by a vulnerability in the service processor mailbox interface. An attacker with authenticated service-level access to the BMC/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.

Weakness: CWE-787

Which versions are affected by CVE-2026-17100?

It affects 29 products.

Products include Ibm Power Hardware Management Console \(7063-Cr2\) Firmware, Ibm Power System Ac922 \(8335-Gth\) Firmware, Ibm Power System Ac922 \(8335-Gtx\) Firmware, Ibm Power System E1050 \(9043-Mrx\) Firmware, Ibm Power System E1080 \(9080-Hex\) Firmware, Ibm Power System E1150 \(9043-Mru\) Firmware and 23 more.

How do I fix CVE-2026-17100?

No fix has been published for CVE-2026-17100 yet. Limit exposure of the affected software until one is available.

Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.

Is CVE-2026-17100 being exploited?

There is no known exploitation of CVE-2026-17100 in the wild and no public exploit code.

Sources

Also known as GHSA-w82q-x75m-xp3p.