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CVE-2026-17042NVD status: Analyzed

Power Systems Firmware: Out-of-bounds Read

Published Updated By the CyberSecBulletin desk

CVE-2026-17042 is a high-severity out-of-bounds read vulnerability in Power Systems Firmware from IBM, with a CVSS 3.1 base score of 7.3 out of 10. It can be exploited with local access to the system by an attacker with a low-privileged account, without any action from a user. Affected Power Systems Firmware versions: FW950.00 through FW950.H2; OP940.00 through OP940.a1; OP940.00 through OP940.81. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.14% chance of exploitation within 30 days, which is low compared with other CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update Power System S922 (9009-22g) Firmware to fw950.h3 or a later version.
  2. Update Power System H922 (9223-22s) Firmware to fw950.h3 or a later version.
  3. Update Power System S914 (9009-41g) Firmware to fw950.h3 or a later version.
  4. Read the advisory on ibm.com for workarounds and exact fixed builds.

Affected products and versions

VendorProductAffected versionsFixed in
IBMPower Systems FirmwareFW950.00 through FW950.H2; OP940.00 through OP940.a1; OP940.00 through OP940.81Not stated
IBMPower System S922 (9009-22g) Firmwarefw950.00 up to, but not including, fw950.h3fw950.h3
IBMPower System H922 (9223-22s) Firmwarefw950.00 up to, but not including, fw950.h3fw950.h3
IBMPower System S914 (9009-41g) Firmwarefw950.00 up to, but not including, fw950.h3fw950.h3
IBMPower System S924 (9009-42g) Firmwarefw950.00 up to, but not including, fw950.h3fw950.h3
IBMPower System H924 (9223-42s) Firmwarefw950.00 up to, but not including, fw950.h3fw950.h3
IBMPower System E950 (9040-mr9) Firmwarefw950.00 up to, but not including, fw950.h3fw950.h3
IBMPower System E980 (9080-m9s) Firmwarefw950.00 up to, but not including, fw950.h3fw950.h3
IBMPower System Ac922 (8335-gth) Firmwareop940 up to, but not including, op940.a2op940.a2
IBMPower System Ac922 (8335-gtx) Firmwareop940 up to, but not including, op940.a2op940.a2
IBMPower Hardware Management Console (7063-cr2) Firmwareop940 up to, but not including, op940.82op940.82

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
LocalThe attacker needs local access or must trick a user into running something.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
LowA basic user account is enough.
User interaction
NoneNo action by a victim is required.
Scope
ChangedThe attack can reach beyond the vulnerable component into other systems.
Confidentiality
NoneNo data is disclosed.
Integrity
LowLimited modification of data is possible.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:N/I:L/A:H. Scored by CNA (us.ibm.com).

Official 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.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Out-of-bounds Read

The product reads data past the end, or before the beginning, of the intended buffer.

How developers prevent this class of flaw

  • Use a language that provides appropriate memory abstractions.

More Out-of-bounds Read vulnerabilities (CWE-125)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: partial).
  3. Record last changed materially (score, affected products, status or references).

References

Other vulnerabilities in Power Systems Firmware

All Power Systems Firmware vulnerabilities

Recent Out-of-bounds Read vulnerabilities

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