CVE-2026-18821
Last modified
CVE-2026-18821 is a high-severity vulnerability rated 8.8/10 on the CVSS scale. 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. EPSS estimates a 0.19% chance of exploitation in the next 30 days.
Description
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.
Metrics
Weakness Enumeration
Affected Software
| Vendor | Product | Versions |
|---|---|---|
| Ibm | Power System S1122 \(9824-22a\) Firmware | >= fw1110.00, < fw1110.31 |
| Ibm | Power System S1122 \(9824-22a\) Firmware | fw1120.00 |
| Ibm | Power System S1124 \(9824-42a\) Firmware | >= fw1110.00, < fw1110.31 |
| Ibm | Power System S1124 \(9824-42a\) Firmware | fw1120.00 |
| Ibm | Power System S1122s \(9824-22b\) Firmware | >= fw1110.00, < fw1110.31 |
| Ibm | Power System S1122s \(9824-22b\) Firmware | fw1120.00 |
| Ibm | Power System S1114 \(9824-41b\) Firmware | >= fw1110.00, < fw1110.31 |
| Ibm | Power System S1114 \(9824-41b\) Firmware | fw1120.00 |
| Ibm | Power System L1122 \(9856-22h\) Firmware | >= fw1110.00, < fw1110.31 |
| Ibm | Power System L1122 \(9856-22h\) Firmware | fw1120.00 |
| Ibm | Power System L1124 \(9856-42h\) Firmware | >= fw1110.00, < fw1110.31 |
| Ibm | Power System L1124 \(9856-42h\) Firmware | fw1120.00 |
| Ibm | Power System E1150 \(9043-Mru\) Firmware | >= fw1110.00, < fw1110.31 |
| Ibm | Power System E1150 \(9043-Mru\) Firmware | fw1120.00 |
| Ibm | Power System S1112 \(9242-21b\) Firmware | fw1120.00 |
| Ibm | Power System S1112 \(9242-21t\) Firmware | fw1120.00 |
| Ibm | Power System E1080 \(9080-Hex\) Firmware | >= fw1060.00, < fw1060.81 |
| Ibm | Power System S1022 \(9105-22a\) Firmware | >= fw1060.00, < fw1060.81 |
| Ibm | Power System S1024 \(9105-42a\) Firmware | >= fw1060.00, < fw1060.81 |
| Ibm | Power System S1022s \(9105-22b\) Firmware | >= fw1060.00, < fw1060.81 |
| Ibm | Power System S1014 \(9105-41b\) Firmware | >= fw1060.00, < fw1060.81 |
| Ibm | Power System L1022 \(9786-22h\) Firmware | >= fw1060.00, < fw1060.81 |
| Ibm | Power System L1024 \(9786-42h\) Firmware | >= fw1060.00, < fw1060.81 |
| Ibm | Power System E1050 \(9043-Mrx\) Firmware | >= fw1060.00, < fw1060.81 |
| Ibm | Power System S1012 \(9028-21b\) Firmware | >= fw1060.00, < fw1060.81 |
| Ibm | Power System E1180 \(9080-Heu\) Firmware | >= fw1110.00, < fw1110.31 |
| Ibm | Power System E1180 \(9080-Heu\) Firmware | fw1120.00 |
| Ibm | Power System S922 \(9009-22g\) Firmware | >= fw950.00, < fw950.h3 |
| Ibm | Power System H922 \(9223-22s\) Firmware | >= fw950.00, < fw950.h3 |
| Ibm | Power System S914 \(9009-41g\) Firmware | >= fw950.00, < fw950.h3 |
| Ibm | Power System S924 \(9009-42g\) Firmware | >= fw950.00, < fw950.h3 |
| Ibm | Power System H924 \(9223-42s\) Firmware | >= fw950.00, < fw950.h3 |
| Ibm | Power System E950 \(9040-Mr9\) Firmware | >= fw950.00, < fw950.h3 |
| Ibm | Power System E980 \(9080-M9s\) Firmware | >= fw950.00, < fw950.h3 |
References
- https://www.ibm.com/support/pages/node/7283232Vendor Advisory
Timeline
- Published
- Last Modified
- Status
- Analyzed
Frequently Asked Questions
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