CVE-2026-102916: Illumos Illumos-Gate

Medium severity, CVSS 6.8. EPSS: 0.1% chance of exploitation in the next 30 days.

A reachable assertion in the illumos bhyve instruction emulator allows a guest to panic the host. When emulating a REP-prefixed MOVS or STOS instruction that accesses guest MMIO, vie_emulate_movs() and vie_emulate_stos() in usr/src/uts/intel/io/vmm/vmm_instruction_emul.c do not clear the VIES_REPEAT status flag on the final iteration. For MMIO regions emulated in the kernel (the local APIC, I/O APIC and HPET), the stale flag causes a VERIFY assertion in vie_advance_pc() to fail, and the host panics. A privileged user within a guest VM can issue a REP MOVS or REP STOS instruction against the local APIC page to cause a denial of service of the host and every other guest running on it. The flaw has existed since 2020 (illumos-gate commit e0c0d44e), and affects any illumos distribution prior to illumos-gate commit 696ecf8d.

Affected products

• Illumos Illumos-Gate
• Omnios Omnios: from r151058, before r151058w (fixed in r151058w); from r151056, before r151056aw (fixed in r151056aw); from r151054, before r151054bw (fixed in r151054bw)

Published 2026-10-09. Last modified 2026-10-09.