Details of VAR-202608-8504

ID

VAR-202608-8504

CVE

CVE-2026-18821

TITLE

IBM of Power System E1050 (9043-MRX) Firmware Out-of-bounds write vulnerabilities in multiple products, including

Trust: 0.8

sources: JVNDB: JVNDB-2026-030371

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. - All information handled by the software may be overwritten. - The software may completely shut down

Trust: 1.62

sources: NVD: CVE-2026-18821 // JVNDB: JVNDB-2026-030371

AFFECTED PRODUCTS

vendor:	ibm	model:	power system s1112 \	scope:	eq	version:	fw1120.00	Trust: 2.0
vendor:	ibm	model:	power system s1112	scope:	-	version:	-	Trust: 1.6
vendor:	ibm	model:	power system l1022 \	scope:	lt	version:	fw1060.81	Trust: 1.0
vendor:	ibm	model:	power system s1022 \	scope:	gte	version:	fw1060.00	Trust: 1.0
vendor:	ibm	model:	power system e1150 \	scope:	lt	version:	fw1110.31	Trust: 1.0
vendor:	ibm	model:	power system e1080 \	scope:	lt	version:	fw1060.81	Trust: 1.0
vendor:	ibm	model:	power system s1124 \	scope:	gte	version:	fw1110.00	Trust: 1.0
vendor:	ibm	model:	power system l1024 \	scope:	gte	version:	fw1060.00	Trust: 1.0
vendor:	ibm	model:	power system s924 \	scope:	gte	version:	fw950.00	Trust: 1.0
vendor:	ibm	model:	power system s1122s \	scope:	lt	version:	fw1110.31	Trust: 1.0
vendor:	ibm	model:	power system s1122 \	scope:	eq	version:	fw1120.00	Trust: 1.0
vendor:	ibm	model:	power system s1114 \	scope:	eq	version:	fw1120.00	Trust: 1.0
vendor:	ibm	model:	power system l1122 \	scope:	lt	version:	fw1110.31	Trust: 1.0
vendor:	ibm	model:	power system s1124 \	scope:	lt	version:	fw1110.31	Trust: 1.0
vendor:	ibm	model:	power system s1122s \	scope:	gte	version:	fw1110.00	Trust: 1.0
vendor:	ibm	model:	power system e1150 \	scope:	gte	version:	fw1110.00	Trust: 1.0
vendor:	ibm	model:	power system l1022 \	scope:	gte	version:	fw1060.00	Trust: 1.0
vendor:	ibm	model:	power system h924 \	scope:	gte	version:	fw950.00	Trust: 1.0
vendor:	ibm	model:	power system e950 \	scope:	lt	version:	fw950.h3	Trust: 1.0
vendor:	ibm	model:	power system h922 \	scope:	gte	version:	fw950.00	Trust: 1.0
vendor:	ibm	model:	power system s1012 \	scope:	lt	version:	fw1060.81	Trust: 1.0
vendor:	ibm	model:	power system l1122 \	scope:	gte	version:	fw1110.00	Trust: 1.0
vendor:	ibm	model:	power system e1080 \	scope:	gte	version:	fw1060.00	Trust: 1.0
vendor:	ibm	model:	power system e1180 \	scope:	eq	version:	fw1120.00	Trust: 1.0
vendor:	ibm	model:	power system s922 \	scope:	lt	version:	fw950.h3	Trust: 1.0
vendor:	ibm	model:	power system s1014 \	scope:	lt	version:	fw1060.81	Trust: 1.0
vendor:	ibm	model:	power system s1012 \	scope:	gte	version:	fw1060.00	Trust: 1.0
vendor:	ibm	model:	power system s1122 \	scope:	lt	version:	fw1110.31	Trust: 1.0
vendor:	ibm	model:	power system s1122 \	scope:	gte	version:	fw1110.00	Trust: 1.0
vendor:	ibm	model:	power system s914 \	scope:	gte	version:	fw950.00	Trust: 1.0
vendor:	ibm	model:	power system s1014 \	scope:	gte	version:	fw1060.00	Trust: 1.0
vendor:	ibm	model:	power system s924 \	scope:	lt	version:	fw950.h3	Trust: 1.0
vendor:	ibm	model:	power system s1114 \	scope:	gte	version:	fw1110.00	Trust: 1.0
vendor:	ibm	model:	power system e980 \	scope:	gte	version:	fw950.00	Trust: 1.0
vendor:	ibm	model:	power system e1050 \	scope:	lt	version:	fw1060.81	Trust: 1.0
vendor:	ibm	model:	power system h922 \	scope:	lt	version:	fw950.h3	Trust: 1.0
vendor:	ibm	model:	power system l1124 \	scope:	eq	version:	fw1120.00	Trust: 1.0
vendor:	ibm	model:	power system s1114 \	scope:	lt	version:	fw1110.31	Trust: 1.0
vendor:	ibm	model:	power system s1022s \	scope:	gte	version:	fw1060.00	Trust: 1.0
vendor:	ibm	model:	power system e1180 \	scope:	lt	version:	fw1110.31	Trust: 1.0
vendor:	ibm	model:	power system h924 \	scope:	lt	version:	fw950.h3	Trust: 1.0
vendor:	ibm	model:	power system e950 \	scope:	gte	version:	fw950.00	Trust: 1.0
vendor:	ibm	model:	power system s1022s \	scope:	lt	version:	fw1060.81	Trust: 1.0
vendor:	ibm	model:	power system e1050 \	scope:	gte	version:	fw1060.00	Trust: 1.0
vendor:	ibm	model:	power system s1122s \	scope:	eq	version:	fw1120.00	Trust: 1.0
vendor:	ibm	model:	power system e1150 \	scope:	eq	version:	fw1120.00	Trust: 1.0
vendor:	ibm	model:	power system e1180 \	scope:	gte	version:	fw1110.00	Trust: 1.0
vendor:	ibm	model:	power system l1122 \	scope:	eq	version:	fw1120.00	Trust: 1.0
vendor:	ibm	model:	power system s1124 \	scope:	eq	version:	fw1120.00	Trust: 1.0
vendor:	ibm	model:	power system s914 \	scope:	lt	version:	fw950.h3	Trust: 1.0
vendor:	ibm	model:	power system l1124 \	scope:	lt	version:	fw1110.31	Trust: 1.0
vendor:	ibm	model:	power system s1024 \	scope:	lt	version:	fw1060.81	Trust: 1.0
vendor:	ibm	model:	power system e980 \	scope:	lt	version:	fw950.h3	Trust: 1.0
vendor:	ibm	model:	power system l1124 \	scope:	gte	version:	fw1110.00	Trust: 1.0
vendor:	ibm	model:	power system s1022 \	scope:	lt	version:	fw1060.81	Trust: 1.0
vendor:	ibm	model:	power system s1024 \	scope:	gte	version:	fw1060.00	Trust: 1.0
vendor:	ibm	model:	power system l1024 \	scope:	lt	version:	fw1060.81	Trust: 1.0
vendor:	ibm	model:	power system s922 \	scope:	gte	version:	fw950.00	Trust: 1.0
vendor:	ibm	model:	power system l1024	scope:	-	version:	-	Trust: 0.8
vendor:	ibm	model:	power system s1022s	scope:	-	version:	-	Trust: 0.8
vendor:	ibm	model:	power system s1122s	scope:	-	version:	-	Trust: 0.8
vendor:	ibm	model:	power system s924	scope:	-	version:	-	Trust: 0.8
vendor:	ibm	model:	power system s1024	scope:	-	version:	-	Trust: 0.8
vendor:	ibm	model:	power system l1124	scope:	-	version:	-	Trust: 0.8
vendor:	ibm	model:	power system e980	scope:	-	version:	-	Trust: 0.8
vendor:	ibm	model:	power system s1124	scope:	-	version:	-	Trust: 0.8
vendor:	ibm	model:	power system e1050	scope:	-	version:	-	Trust: 0.8
vendor:	ibm	model:	power system e1080	scope:	-	version:	-	Trust: 0.8
vendor:	ibm	model:	power system s1122	scope:	-	version:	-	Trust: 0.8
vendor:	ibm	model:	power system l1022	scope:	-	version:	-	Trust: 0.8
vendor:	ibm	model:	power system s1114	scope:	-	version:	-	Trust: 0.8
vendor:	ibm	model:	power system e1180	scope:	-	version:	-	Trust: 0.8
vendor:	ibm	model:	power system s1012	scope:	-	version:	-	Trust: 0.8
vendor:	ibm	model:	power system l1122	scope:	-	version:	-	Trust: 0.8
vendor:	ibm	model:	power system h924	scope:	-	version:	-	Trust: 0.8
vendor:	ibm	model:	power system e1150	scope:	-	version:	-	Trust: 0.8
vendor:	ibm	model:	power system s1014	scope:	-	version:	-	Trust: 0.8
vendor:	ibm	model:	power system h922	scope:	-	version:	-	Trust: 0.8
vendor:	ibm	model:	power system s1022	scope:	-	version:	-	Trust: 0.8
vendor:	ibm	model:	power system s922	scope:	-	version:	-	Trust: 0.8
vendor:	ibm	model:	power system s914	scope:	-	version:	-	Trust: 0.8
vendor:	ibm	model:	power system e950	scope:	-	version:	-	Trust: 0.8

sources: JVNDB: JVNDB-2026-030371 // NVD: CVE-2026-18821

CVSS

SEVERITY

CVSSV2

CVSSV3

psirt@us.ibm.com:	CVE-2026-18821
value:	HIGH
Trust: 1.0
nvd@nist.gov:	CVE-2026-18821
value:	HIGH
Trust: 1.0
NVD:	CVE-2026-18821
value:	HIGH
Trust: 0.8

psirt@us.ibm.com:	CVE-2026-18821
baseSeverity:	HIGH
baseScore:	7.5
vectorString:	CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
attackVector:	ADJACENT
attackComplexity:	HIGH
privilegesRequired:	NONE
userInteraction:	NONE
scope:	UNCHANGED
confidentialityImpact:	HIGH
integrityImpact:	HIGH
availabilityImpact:	HIGH
exploitabilityScore:	1.6
impactScore:	5.9
version:	3.1
Trust: 1.0
nvd@nist.gov:	CVE-2026-18821
baseSeverity:	HIGH
baseScore:	8.8
vectorString:	CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
attackVector:	ADJACENT
attackComplexity:	LOW
privilegesRequired:	NONE
userInteraction:	NONE
scope:	UNCHANGED
confidentialityImpact:	HIGH
integrityImpact:	HIGH
availabilityImpact:	HIGH
exploitabilityScore:	2.8
impactScore:	5.9
version:	3.1
Trust: 1.0
NVD:	CVE-2026-18821
baseSeverity:	HIGH
baseScore:	8.8
vectorString:	CVSS:3.0/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
attackVector:	ADJACENT NETWORK
attackComplexity:	LOW
privilegesRequired:	NONE
userInteraction:	NONE
scope:	UNCHANGED
confidentialityImpact:	HIGH
integrityImpact:	HIGH
availabilityImpact:	HIGH
exploitabilityScore:	NONE
impactScore:	NONE
version:	3.0
Trust: 0.8

sources: JVNDB: JVNDB-2026-030371 // NVD: CVE-2026-18821 // NVD: CVE-2026-18821

PROBLEMTYPE DATA

problemtype:	CWE-787	Trust: 1.0
problemtype:	Out-of-bounds writing (CWE-787) [ others ]	Trust: 0.8

sources: JVNDB: JVNDB-2026-030371 // NVD: CVE-2026-18821

PATCH

title:

Security Bulletin

url:

https://www.ibm.com/support/pages/node/7283232

Trust: 0.8

sources: JVNDB: JVNDB-2026-030371

EXTERNAL IDS

db:	NVD	id:	CVE-2026-18821	Trust: 2.6
db:	JVNDB	id:	JVNDB-2026-030371	Trust: 0.8

sources: JVNDB: JVNDB-2026-030371 // NVD: CVE-2026-18821

REFERENCES

url:	https://www.ibm.com/support/pages/node/7283232	Trust: 1.0
url:	https://nvd.nist.gov/vuln/detail/cve-2026-18821	Trust: 0.8

sources: JVNDB: JVNDB-2026-030371 // NVD: CVE-2026-18821

SOURCES

db:	JVNDB	id:	JVNDB-2026-030371
db:	NVD	id:	CVE-2026-18821

LAST UPDATE DATE

2026-08-27T23:55:24.853000+00:00

SOURCES UPDATE DATE

db:	JVNDB	id:	JVNDB-2026-030371	date:	2026-08-26T07:28:00
db:	NVD	id:	CVE-2026-18821	date:	2026-08-25T20:40:39.927

SOURCES RELEASE DATE

db:	JVNDB	id:	JVNDB-2026-030371	date:	2026-08-26T00:00:00
db:	NVD	id:	CVE-2026-18821	date:	2026-08-19T20:17:13.603