Firmware-level arbitrary code execution on IBM Power servers via FSP mailbox allows full system compromise of enterprise hardware used across many organizations.
CVE-2026-96262
Authenticated attacker can run arbitrary code in IBM Power host firmware via FSP mailbox overflow.
Is CVE-2026-96262 being exploited?
Not confirmed. CVE-2026-96262 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 0.17% probability of exploitation in the next 30 days.
How severe is CVE-2026-96262?
CVE-2026-96262 is rated High with a CVSS score of 8.2. 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-2026-96262?
Yes. A fix has been recorded for CVE-2026-96262. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-96262 affect?
CVE-2026-96262 affects IBM Power Systems Firmware FW1060.00 through FW1060.81 (FSP service processor). Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-96262?
Install IBM firmware update immediately; restrict FSP service access; monitor logs.
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Authenticated service-level user can overflow the FSP mailbox to execute arbitrary code in host firmware, gaining full memory and hardware access and total system compromise.
Immediate action required
- affected>= FW1060.00 and <= FW1060.81
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.