CVE-2026-17091
Guest-root can crash or corrupt IBM PowerVM via crafted hypercall.
Is CVE-2026-17091 being exploited?
Not confirmed. CVE-2026-17091 does not appear in CISA's Known Exploited Vulnerabilities catalog, which records only exploitation that has been observed and reported publicly. That is evidence of absence of a report, not evidence the flaw is unattacked. EPSS currently estimates a 0.12% probability of exploitation in the next 30 days.
How severe is CVE-2026-17091?
CVE-2026-17091 is rated High with a CVSS score of 8.4. Severity describes how bad exploitation would be, not how likely it is: pair it with exploitation evidence before deciding what to patch first.
Is there a patch for CVE-2026-17091?
Yes. A fix has been recorded for CVE-2026-17091. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-17091 affect?
CVE-2026-17091 affects IBM PowerVM Hypervisor FW1120.00, IBM PowerVM Hypervisor FW1110.00-FW1110.30, IBM PowerVM Hypervisor FW1060.00-FW1060.80, IBM PowerVM Hypervisor FW950.00-FW950.H2, and 1 further product or version. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-17091?
Restrict guest root, isolate vulnerable hosts, and apply vendor patch when released.
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
A guest with root can inject arbitrary data via a hypercall, causing hypervisor/partition memory corruption or full platform re-IPL (availability and integrity loss).
Immediate action required
- affectedFW1120.00
- affected>= FW1110.00 and <= FW1110.30
- affected>= FW1060.00 and <= FW1060.80
- affected>= FW950.00 and <= FW950.H2
As published in the CVE Program record. A version outside these ranges is not a statement that it is unaffected — vendors sometimes understate a range, and distribution-backported builds carry upstream numbers that do not reflect what was patched into them.