IBM Power Systems Firmware NVRAM parsing flaw (FW950, OP940) Crash & Memory Corrupt
CVE-2026-17042 Published on August 19, 2026
Power System Out-of-bounds Read
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.
Vulnerability Analysis
CVE-2026-17042 is exploitable with local system access, and requires small amount of user privileges. This vulnerability is considered to have a low attack complexity. The potential impact of an exploit of this vulnerability is considered to have no impact on confidentiality, with no impact on integrity, and a high impact on availability.
Weakness Type
Out-of-bounds Read
The software reads data past the end, or before the beginning, of the intended buffer. Typically, this can allow attackers to read sensitive information from other memory locations or cause a crash. A crash can occur when the code reads a variable amount of data and assumes that a sentinel exists to stop the read operation, such as a NUL in a string. The expected sentinel might not be located in the out-of-bounds memory, causing excessive data to be read, leading to a segmentation fault or a buffer overflow. The software may modify an index or perform pointer arithmetic that references a memory location that is outside of the boundaries of the buffer. A subsequent read operation then produces undefined or unexpected results.
Products Associated with CVE-2026-17042
Want to know whenever a new CVE is published for IBM Power Systems Firmware? stack.watch will email you.
Affected Versions
IBM Power Systems Firmware:- Version FW950.00, <= FW950.H2 is affected.
- Version OP940.00, <= OP940.a1 is affected.
- Version OP940.00, <= OP940.81 is affected.