CVE-2026-18821CWE-787

CVE-2026-18821

High · published August 20, 2026

CVSS v3.1
7.5
EPSS
0%
Percentile
8.8
In the wild
Unconfirmed
What it is

IBM PowerVM Hypervisor FW1120.00, FW1110.00 through FW1110.30, FW1060.00 through FW1060.80, and FW950.00 through FW950.H2 Power Systems Firmware is affected by a vulnerability in partition firmware during network boot. An unauthenticated attacker on the same network as a partition undergoing network boot can send a malformed packet, allowing arbitrary code to be executed in the partition firmware and compromising everything subsequently loaded by that partition. Other partitions and the managed system are not affected. Only partitions actively performing a network boot are affected, resulting in a confidentiality, integrity, and availability impact.

The record
Technical detail
CVSS v3.1
7.5 · HIGH
Vector
CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
CVSS v4.0
Not supplied
EPSS
0.00196 · 8.8th percentile
Weakness
CWE-787 · Out-of-bounds Write
Published
2026-08-20T00:17Z
Affected products (34)
ProductVersionsFixed in
ibm/power_system_s1122_\(9824-22a\)_firmware≥ fw1110.00, < fw1110.31fw1110.31
ibm/power_system_s1122_\(9824-22a\)_firmwareall versions—
ibm/power_system_s1124_\(9824-42a\)_firmware≥ fw1110.00, < fw1110.31fw1110.31
ibm/power_system_s1124_\(9824-42a\)_firmwareall versions—
ibm/power_system_s1122s_\(9824-22b\)_firmware≥ fw1110.00, < fw1110.31fw1110.31
ibm/power_system_s1122s_\(9824-22b\)_firmwareall versions—
ibm/power_system_s1114_\(9824-41b\)_firmware≥ fw1110.00, < fw1110.31fw1110.31
ibm/power_system_s1114_\(9824-41b\)_firmwareall versions—
ibm/power_system_l1122_\(9856-22h\)_firmware≥ fw1110.00, < fw1110.31fw1110.31
ibm/power_system_l1122_\(9856-22h\)_firmwareall versions—
ibm/power_system_l1124_\(9856-42h\)_firmware≥ fw1110.00, < fw1110.31fw1110.31
ibm/power_system_l1124_\(9856-42h\)_firmwareall versions—
ibm/power_system_e1150_\(9043-mru\)_firmware≥ fw1110.00, < fw1110.31fw1110.31
ibm/power_system_e1150_\(9043-mru\)_firmwareall versions—
ibm/power_system_s1112_\(9242-21b\)_firmwareall versions—
ibm/power_system_s1112_\(9242-21t\)_firmwareall versions—
ibm/power_system_e1080_\(9080-hex\)_firmware≥ fw1060.00, < fw1060.81fw1060.81
ibm/power_system_s1022_\(9105-22a\)_firmware≥ fw1060.00, < fw1060.81fw1060.81
ibm/power_system_s1024_\(9105-42a\)_firmware≥ fw1060.00, < fw1060.81fw1060.81
ibm/power_system_s1022s_\(9105-22b\)_firmware≥ fw1060.00, < fw1060.81fw1060.81
ibm/power_system_s1014_\(9105-41b\)_firmware≥ fw1060.00, < fw1060.81fw1060.81
ibm/power_system_l1022_\(9786-22h\)_firmware≥ fw1060.00, < fw1060.81fw1060.81
ibm/power_system_l1024_\(9786-42h\)_firmware≥ fw1060.00, < fw1060.81fw1060.81
ibm/power_system_e1050_\(9043-mrx\)_firmware≥ fw1060.00, < fw1060.81fw1060.81
ibm/power_system_s1012_\(9028-21b\)_firmware≥ fw1060.00, < fw1060.81fw1060.81
ibm/power_system_e1180_\(9080-heu\)_firmware≥ fw1110.00, < fw1110.31fw1110.31
ibm/power_system_e1180_\(9080-heu\)_firmwareall versions—
ibm/power_system_s922_\(9009-22g\)_firmware≥ fw950.00, < fw950.h3fw950.h3
ibm/power_system_h922_\(9223-22s\)_firmware≥ fw950.00, < fw950.h3fw950.h3
ibm/power_system_s914_\(9009-41g\)_firmware≥ fw950.00, < fw950.h3fw950.h3
ibm/power_system_s924_\(9009-42g\)_firmware≥ fw950.00, < fw950.h3fw950.h3
ibm/power_system_h924_\(9223-42s\)_firmware≥ fw950.00, < fw950.h3fw950.h3
ibm/power_system_e950_\(9040-mr9\)_firmware≥ fw950.00, < fw950.h3fw950.h3
ibm/power_system_e980_\(9080-m9s\)_firmware≥ fw950.00, < fw950.h3fw950.h3
References (1)
EPSS history
Timeline
  • 19 AUG 19:41Z
    Power System Out-of-bounds Write
    cvelistv5