Description
IBM Power Systems Firmware FW950.00 through FW950.H2, OP940.00 through OP940.a1 (Power9), and OP940.00 - OP940.81 (Power HMC) is affected by a vulnerability in host firmware NVRAM parsing. An attacker with root access to a guest partition on an OpenPOWER system can write a specially crafted NVRAM image, causing the host firmware boot stage to crash with possible memory corruption. This condition persists until operator intervention — clearing NVRAM via the service processor — to restore normal operation. This vulnerability only affects OpenPOWER systems; systems running PowerVM are not affected. Successful exploitation results in an integrity and availability impact to the managed system.
Affected products
ibm: power system s922 \(9009-22g\) firmware; ibm: power system s922 \(9009-22g\); ibm: power system h922 \(9223-22s\) firmware; ibm: power system h922 \(9223-22s\); ibm: power system s914 \(9009-41g\) firmware; ibm: power system s914 \(9009-41g\); ibm: power system s924 \(9009-42g\) firmware; ibm: power system s924 \(9009-42g\); ibm: power system h924 \(9223-42s\) firmware; ibm: power system h924 \(9223-42s\); ibm: power system e950 \(9040-mr9\) firmware; ibm: power system e950 \(9040-mr9\); ibm: power system e980 \(9080-m9s\) firmware; ibm: power system e980 \(9080-m9s\); ibm: power system ac922 \(8335-gth\) firmware
References1
- www.ibm.com/support/pages/node/7283240 Vendor Advisory
Metrics
- CVSS 3.1
-
7.3
HIGH
Score source: NVD
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:N/I:L/A:H - EPSS — exploit probability
- 0% percentile: 3 · as of 10 November 2026
- CWE
- CWE-125
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