Evidence used
- No CISA KEV confirmation is currently recorded.
- Exploitation requires an existing local or physical foothold with privileges.
- EPSS is 0.10% for the current model date.
BlackTreeCVE IntelligenceFull vulnerability report · 2026
CVE-2026-17504High confidence
This Power System update is being released to address
IBM · PowerVM Hypervisor
5.1MediumCVSS 3.1
Scheduled
Patch availableMedium technical severity with no CISA KEV confirmation; remediate through the normal risk-based patch cycle unless local exposure raises the priority.
R
Open reassessment dashboard →Operational reassessment
Published severity in operational context
Published severityMedium→Operational priority:Low, lowered one band.downgradedsince 24 Sep 2026
Compensating controls
- Validate the affected product branch and deploy the verified fixed release.
- Restrict local access and enforce least privilege on affected hosts.
- Monitor vendor guidance and exploitation sources for a material change.
Verification
- Confirm that the asset runs IBM PowerVM Hypervisor and falls inside the recorded affected range.
- Verify the installed build against the product-specific fixed version after deployment.
- Validate exposure, authentication requirements and compensating controls in the actual environment.
- Reopen this reassessment when CVSS, KEV, EPSS, exploit evidence or remediation changes.
Medium technical severity with no CISA KEV confirmation; remediate through the normal risk-based patch cycle unless local exposure raises the priority.
Patch available01
What, why and how
IBM PowerVM Hypervisor FW1120.00 through FW1120.01, FW1110.00 through FW1110.31, FW1060.00 through FW1060.81, and FW950.00 through FW950.H3 is affected by a vulnerability in the partition firmware runtime. An attacker with root access to a partition can send a specially crafted request to the partition firmware runtime, causing it to crash with possible memory corruption.
What
IBM PowerVM Hypervisor FW1120.00 through FW1120.01, FW1110.00 through FW1110.31, FW1060.00 through FW1060.81, and FW950.00 through FW950.H3 is affected by a vulnerability in the partition firmware runtime. An attacker with root access to a partition can send a specially crafted request to the partition firmware runtime, causing it to crash with possible memory corruption.
Why
The product subtracts one value from another, such that the result is less than the minimum allowable integer value, which produces a value that is not equal to the correct result.
How
An attacker operating through local access may attempt exploitation with elevated privileges. If successful, the issue may disrupt the affected service.
What
IBM PowerVM Hypervisor FW1120.00 through FW1120.01, FW1110.00 through FW1110.31, FW1060.00 through FW1060.81, and FW950.00 through FW950.H3 is affected by a vulnerability in the partition firmware runtime. An attacker with root access to a partition can send a specially crafted request to the partition firmware runtime, causing it to crash with possible memory corruption.
Why
The product subtracts one value from another, such that the result is less than the minimum allowable integer value, which produces a value that is not equal to the correct result.
How
An attacker operating through local access may attempt exploitation with elevated privileges. If successful, the issue may disrupt the affected service.
02
Exploit reality and attack path
CVSS severity, EPSS forecast probability, public exploit material and CISA-confirmed exploitation are separate signals.
Observed exploitation No confirmed evidence
?
Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.No CISA KEV match was present at the last successful refresh. This means no confirmation from that source, not proof of no exploitation.
Public PoC / exploit material None recorded
?
Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.No exploit-tagged reference or CISA SSVC proof-of-concept state is currently recorded. Research may still exist outside the structured feeds.
- Likely attack path
- local access → Integer Underflow (Wrap or Wraparound) → disrupt the affected service
- Attack surface
- Local
- Privileges required
- High: elevated access is required
- User interaction
- None
- Attack complexity
- Low: no specialised conditions are recorded
- Security boundary
- Unchanged: impact remains within the vulnerable component's security authority
- Weakness
?
CWE means Common Weakness Enumeration: a standard category for the underlying weakness. - CWE-191 ↗
CWE-191: Integer Underflow (Wrap or Wraparound). The product subtracts one value from another, such that the result is less than the minimum allowable integer value, which produces a value that is not equal to the correct result.
- CVSS vector
?
CVSS means Common Vulnerability Scoring System. The vector records the metric values used to calculate technical severity. CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:N/I:L/A:HCommon Vulnerability Scoring System 3.1: the compact vector below is decoded into plain language.
AVLocalAttack vector: The attacker needs local access to the vulnerable system.ACLowAttack complexity: No specialised conditions are required beyond attacker-controlled input.PRHighPrivileges required: The attacker needs elevated or administrative privileges.UINoneUser interaction: No action by another user is required.SUnchangedScope: The security impact remains within the vulnerable component's authority.CNoneConfidentiality impact: No direct loss is represented by this metric.ILowIntegrity impact: A successful attack can cause a limited loss.AHighAvailability impact: A successful attack can cause a major loss.- Post-exploitation / living off the land
- The issue can support a local privilege or sandbox boundary transition; normal system utilities may then be available in the gained context.
03
Patch and workaround
Operational remediation based on structured source evidence.
- Status
?
Patch availability is based on structured fixed-version fields and authoritative update references. If no fix is verified, check the vendor advisory before making a change. - Patch available
- Fixed
- Customers with the products below should install FW1110.32(1110_138), FW1120.02(1120_171), or newer to remediate this vulnerability.
- Power 11
- * IBM Power System E1180 (9080-HEU)
- Customers with the products below should install FW1110.32(1110_160), FW1120.02(1120_195), or newer to remediate this vulnerability.
- * IBM Power System S1122 (9824-22A)
- * IBM Power System S1124 (9824-42A)
- * IBM Power System S1122s (9824-22B)
- * IBM Power System S1114 (9824-41B)
- * IBM Power System L1122 (9856-22H)
- * IBM Power System L1124 (9856-42H)
- * IBM Power System E1150 (9043-MRU)
- Customers with the products below should install FW1120.02(1120_195), or newer to remediate this vulnerability.
- Action
- Review the linked authoritative reference and apply the recorded fixed release appropriate to the affected product branch.
- Workaround
- No verified workaround is recorded. Limit untrusted access and use least privilege until authoritative guidance is available.
Official vendor articles1 stored document
Linked articles are downloaded and versioned as source evidence. A CVE mention or approved update relationship does not, by itself, verify a fix for every product branch.
- Security Bulletin: This Power System update is being released to address CVE-2026-17504 →Original publisher ↗Searchable text snapshot · Captured 29 Sep 2026IBM Support No results were found for your search query. Tips To return expected results, you can: Reduce the number of search terms. Each term you use focuses the search further. Check your spelling. A single misspelled or incorrectly typed term can change your result. Try substituting synonyms for your original ter
04
Evidence and provenance
Published 24 Sept 2026 · Last source change 24 Sept 2026, 14:31 UTC · CWE-191 · Integer Underflow (Wrap or Wraparound)
CVE recordCVE.org · 5.2
CVSS sourceCNA
EPSS source FIRST · tracked since 2026-09-25
?
The date BlackTree first stored a score for this CVE from the daily FIRST EPSS feed.European sourceENISA EUVD · EUVD-2026-85890
Product sourceCNA
Remediation sourceCVE/CNA references
CWE sourceCNA
NVD statusNVD enrichment underway
Core structured fields are present and their contributing authorities are shown above.
Material change intelligence
View recent updates ↗What changed after publication
- ENISA EUVD mappingEUVD-2026-85890 was added to the official ENISA EUVD mapping for this CVE.ENISA EUVD ↗
- Before
- not recorded
- After
- {"euvdId":"EUVD-2026-85890"}
- Vendor guidanceAuthoritative vendor guidance changed: added patch: ibm.com/7289130.psirt@us.ibm.com ↗
- Before
- remediation: ibm.com/7289130
- After
- patch: ibm.com/7289130 · remediation: ibm.com/7289130
- Vendor guidanceAuthoritative vendor guidance changed: added remediation: ibm.com/7289130.CNA ↗
- Before
- no authoritative guidance recorded
- After
- remediation: ibm.com/7289130
- Affected versionsThe structured affected or fixed version information changed.CNA ↗
- Before
- PowerVM Hypervisor: FW1120.00 ≤ FW1120.01, FW1110.00 ≤ FW1110.31, FW1060.00 ≤ FW1060.81, FW950.00 ≤ FW950.H3 · Fixed: No fixed version is explicitly recorded in the structured CVE data.
- After
- PowerVM Hypervisor: FW1120.00 ≤ FW1120.01, FW1110.00 ≤ FW1110.31, FW1060.00 ≤ FW1060.81, FW950.00 ≤ FW950.H3 · Fixed: Customers with the products below should install FW1110.32(1110_138), FW1120.02(1120_171), or newer to remediate this vulnerability.; Power 11; * IBM Power System E1180 (9080-HEU); Customers with the products below should install FW1110.32(1110_160), FW1120.02(1120_195), or newer to remediate this vulnerability.; * IBM Power System S1122 (9824-22A); * IBM Power System S1124 (9824-42A); * IBM Power System S1122s (9824-22B); * IBM Power System S1114 (9824-41B); * IBM Power System L1122 (9856-22H); * IBM Power System L1124 (9856-42H); * IBM Power System E1150 (9043-MRU); Customers with the products below should install FW1120.02(1120_195), or newer to remediate this vulnerability.
- Remediation statusRemediation status changed from Awaiting fix to Patch available.CNA ↗
- Before
- Awaiting fix
- After
- Patch available
- Catalogue recordCVE added to the BlackTree catalogue.CNA ↗
CVE published
Fixed release or patch reference recorded
Technical terms and abbreviations used in this report
- CVE
- Common Vulnerabilities and Exposures: the public identifier for one disclosed vulnerability.
- CVSS
- Common Vulnerability Scoring System: a technical severity framework; it is not patching priority by itself.
- EPSS
- Exploit Prediction Scoring System: FIRST's estimate of the probability that exploitation activity will be observed in the next 30 days; it is a forecast, not confirmation.
- CWE
- Common Weakness Enumeration: the standard category describing the underlying software or hardware weakness.
- CNA
- CVE Numbering Authority: an organisation authorised to assign and publish CVE records.
- CISA ADP
- Cybersecurity and Infrastructure Security Agency Authorized Data Publisher: structured enrichment added to a CVE record.
- NVD
- National Vulnerability Database: NIST's enrichment service for CVE records.
- CERT / CSIRT
- A computer security incident response team that publishes warnings or coordinates incident response.
- PoC
- Proof of concept: public material that demonstrates or helps reproduce exploitation.
- CSAF
- Common Security Advisory Framework: a machine-readable format for security advisories.
- LoTL
- Living off the land: abuse of legitimate tools or system functions during an attack.